diff --git a/Doc/library/__builtin__.rst b/Doc/library/__builtin__.rst
index b3e1e11..5c89c0c 100644
--- a/Doc/library/__builtin__.rst
+++ b/Doc/library/__builtin__.rst
@@ -33,9 +33,10 @@
 
        # ...
 
-As an implementation detail, most modules have the name ``__builtins__`` (note
-the ``'s'``) made available as part of their globals.  The value of
-``__builtins__`` is normally either this module or the value of this modules's
-:attr:`__dict__` attribute.  Since this is an implementation detail, it may not
-be used by alternate implementations of Python.
+.. impl-detail::
 
+   Most modules have the name ``__builtins__`` (note the ``'s'``) made available
+   as part of their globals.  The value of ``__builtins__`` is normally either
+   this module or the value of this modules's :attr:`__dict__` attribute.  Since
+   this is an implementation detail, it may not be used by alternate
+   implementations of Python.
diff --git a/Doc/library/codecs.rst b/Doc/library/codecs.rst
index 89d6610..ef486f7 100644
--- a/Doc/library/codecs.rst
+++ b/Doc/library/codecs.rst
@@ -54,7 +54,7 @@
    *incrementalencoder* and *incrementaldecoder*: These have to be factory
    functions providing the following interface:
 
-   ``factory(errors='strict')``
+      ``factory(errors='strict')``
 
    The factory functions must return objects providing the interfaces defined by
    the base classes :class:`IncrementalEncoder` and :class:`IncrementalDecoder`,
@@ -63,20 +63,24 @@
    *streamreader* and *streamwriter*: These have to be factory functions providing
    the following interface:
 
-   ``factory(stream, errors='strict')``
+      ``factory(stream, errors='strict')``
 
    The factory functions must return objects providing the interfaces defined by
    the base classes :class:`StreamWriter` and :class:`StreamReader`, respectively.
    Stream codecs can maintain state.
 
-   Possible values for errors are ``'strict'`` (raise an exception in case of an
-   encoding error), ``'replace'`` (replace malformed data with a suitable
-   replacement marker, such as ``'?'``), ``'ignore'`` (ignore malformed data and
-   continue without further notice), ``'xmlcharrefreplace'`` (replace with the
-   appropriate XML character reference (for encoding only)) and
-   ``'backslashreplace'`` (replace with backslashed escape sequences (for encoding
-   only)) as well as any other error handling name defined via
-   :func:`register_error`.
+   Possible values for errors are
+
+   * ``'strict'``: raise an exception in case of an encoding error
+   * ``'replace'``: replace malformed data with a suitable replacement marker,
+     such as ``'?'`` or ``'\ufffd'``
+   * ``'ignore'``: ignore malformed data and continue without further notice
+   * ``'xmlcharrefreplace'``: replace with the appropriate XML character
+     reference (for encoding only)
+   * ``'backslashreplace'``: replace with backslashed escape sequences (for
+     encoding only
+
+   as well as any other error handling name defined via :func:`register_error`.
 
    In case a search function cannot find a given encoding, it should return
    ``None``.
@@ -177,27 +181,33 @@
 
 .. function:: strict_errors(exception)
 
-   Implements the ``strict`` error handling.
+   Implements the ``strict`` error handling: each encoding or decoding error
+   raises a :exc:`UnicodeError`.
 
 
 .. function:: replace_errors(exception)
 
-   Implements the ``replace`` error handling.
+   Implements the ``replace`` error handling: malformed data is replaced with a
+   suitable replacement character such as ``'?'`` in bytestrings and
+   ``'\ufffd'`` in Unicode strings.
 
 
 .. function:: ignore_errors(exception)
 
-   Implements the ``ignore`` error handling.
+   Implements the ``ignore`` error handling: malformed data is ignored and
+   encoding or decoding is continued without further notice.
 
 
 .. function:: xmlcharrefreplace_errors(exception)
 
-   Implements the ``xmlcharrefreplace`` error handling.
+   Implements the ``xmlcharrefreplace`` error handling (for encoding only): the
+   unencodable character is replaced by an appropriate XML character reference.
 
 
 .. function:: backslashreplace_errors(exception)
 
-   Implements the ``backslashreplace`` error handling.
+   Implements the ``backslashreplace`` error handling (for encoding only): the
+   unencodable character is replaced by a backslashed escape sequence.
 
 To simplify working with encoded files or stream, the module also defines these
 utility functions:
diff --git a/Doc/library/configparser.rst b/Doc/library/configparser.rst
index c3b5b8f..878685c 100644
--- a/Doc/library/configparser.rst
+++ b/Doc/library/configparser.rst
@@ -317,12 +317,23 @@
 
 .. method:: RawConfigParser.optionxform(option)
 
-   Transforms the option name *option* as found in an input file or as passed in by
-   client code to the form that should be used in the internal structures.  The
-   default implementation returns a lower-case version of *option*; subclasses may
-   override this or client code can set an attribute of this name on instances to
-   affect this behavior.  Setting this to :func:`str`, for example, would make
-   option names case sensitive.
+   Transforms the option name *option* as found in an input file or as passed in
+   by client code to the form that should be used in the internal structures.
+   The default implementation returns a lower-case version of *option*;
+   subclasses may override this or client code can set an attribute of this name
+   on instances to affect this behavior.
+
+   You don't necessarily need to subclass a ConfigParser to use this method, you
+   can also re-set it on an instance, to a function that takes a string
+   argument.  Setting it to ``str``, for example, would make option names case
+   sensitive::
+
+      cfgparser = ConfigParser()
+      ...
+      cfgparser.optionxform = str
+
+   Note that when reading configuration files, whitespace around the
+   option names are stripped before :meth:`optionxform` is called.
 
 
 .. _configparser-objects:
diff --git a/Doc/library/curses.rst b/Doc/library/curses.rst
index fa66d1e..a2519f4 100644
--- a/Doc/library/curses.rst
+++ b/Doc/library/curses.rst
@@ -1,13 +1,13 @@
-
 :mod:`curses` --- Terminal handling for character-cell displays
 ===============================================================
 
 .. module:: curses
-   :synopsis: An interface to the curses library, providing portable terminal handling.
+   :synopsis: An interface to the curses library, providing portable terminal
+              handling.
+   :platform: Unix
 .. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
 .. sectionauthor:: Eric Raymond <esr@thyrsus.com>
 
-
 .. versionchanged:: 1.6
    Added support for the ``ncurses`` library and converted to a package.
 
diff --git a/Doc/library/datetime.rst b/Doc/library/datetime.rst
index 7251479..54fa755 100644
--- a/Doc/library/datetime.rst
+++ b/Doc/library/datetime.rst
@@ -235,7 +235,7 @@
 |                                | (-*t1.days*, -*t1.seconds*,                   |
 |                                | -*t1.microseconds*), and to *t1*\* -1. (1)(4) |
 +--------------------------------+-----------------------------------------------+
-| ``abs(t)``                     | equivalent to +*t* when ``t.days >= 0``, and  |
+| ``abs(t)``                     | equivalent to +\ *t* when ``t.days >= 0``, and|
 |                                | to -*t* when ``t.days < 0``. (2)              |
 +--------------------------------+-----------------------------------------------+
 
diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst
index 6892c65..96eff1e 100644
--- a/Doc/library/functions.rst
+++ b/Doc/library/functions.rst
@@ -523,8 +523,10 @@
 
    Return the "identity" of an object.  This is an integer (or long integer) which
    is guaranteed to be unique and constant for this object during its lifetime.
-   Two objects with non-overlapping lifetimes may have the same :func:`id` value.
-   (Implementation note: this is the address of the object.)
+   Two objects with non-overlapping lifetimes may have the same :func:`id`
+   value.
+
+   .. impl-detail:: This is the address of the object.
 
 
 .. function:: input([prompt])
@@ -1377,14 +1379,15 @@
    elements are never used (such as when the loop is usually terminated with
    :keyword:`break`).
 
-   .. note::
+   .. impl-detail::
 
-      :func:`xrange` is intended to be simple and fast. Implementations may impose
-      restrictions to achieve this. The C implementation of Python restricts all
-      arguments to native C longs ("short" Python integers), and also requires that
-      the number of elements fit in a native C long.  If a larger range is needed,
-      an alternate version can be crafted using the :mod:`itertools` module:
-      ``islice(count(start, step), (stop-start+step-1)//step)``.
+      :func:`xrange` is intended to be simple and fast.  Implementations may
+      impose restrictions to achieve this.  The C implementation of Python
+      restricts all arguments to native C longs ("short" Python integers), and
+      also requires that the number of elements fit in a native C long.  If a
+      larger range is needed, an alternate version can be crafted using the
+      :mod:`itertools` module: ``islice(count(start, step),
+      (stop-start+step-1)//step)``.
 
 
 .. function:: zip([iterable, ...])
diff --git a/Doc/library/getopt.rst b/Doc/library/getopt.rst
index 2c0fad9..927953c 100644
--- a/Doc/library/getopt.rst
+++ b/Doc/library/getopt.rst
@@ -30,19 +30,20 @@
 
    .. note::
 
-      Unlike GNU :cfunc:`getopt`, after a non-option argument, all further arguments
-      are considered also non-options. This is similar to the way non-GNU Unix systems
-      work.
+      Unlike GNU :cfunc:`getopt`, after a non-option argument, all further
+      arguments are considered also non-options. This is similar to the way
+      non-GNU Unix systems work.
 
    *long_options*, if specified, must be a list of strings with the names of the
-   long options which should be supported.  The leading ``'-``\ ``-'`` characters
-   should not be included in the option name.  Long options which require an
-   argument should be followed by an equal sign (``'='``).  To accept only long
-   options, *options* should be an empty string.  Long options on the command line
-   can be recognized so long as they provide a prefix of the option name that
-   matches exactly one of the accepted options.  For example, if *long_options* is
-   ``['foo', 'frob']``, the option :option:`--fo` will match as :option:`--foo`,
-   but :option:`--f` will not match uniquely, so :exc:`GetoptError` will be raised.
+   long options which should be supported.  The leading ``'-``\ ``-'``
+   characters should not be included in the option name.  Long options which
+   require an argument should be followed by an equal sign (``'='``).  Optional
+   arguments are not supported.  To accept only long options, *options* should
+   be an empty string.  Long options on the command line can be recognized so
+   long as they provide a prefix of the option name that matches exactly one of
+   the accepted options.  For example, if *long_options* is ``['foo', 'frob']``,
+   the option :option:`--fo` will match as :option:`--foo`, but :option:`--f`
+   will not match uniquely, so :exc:`GetoptError` will be raised.
 
    The return value consists of two elements: the first is a list of ``(option,
    value)`` pairs; the second is the list of program arguments left after the
diff --git a/Doc/library/inspect.rst b/Doc/library/inspect.rst
index 3619235..d85ac60 100644
--- a/Doc/library/inspect.rst
+++ b/Doc/library/inspect.rst
@@ -353,9 +353,11 @@
 
    Return true if the object is a getset descriptor.
 
-   getsets are attributes defined in extension modules via ``PyGetSetDef``
-   structures.  For Python implementations without such types, this method will
-   always return ``False``.
+   .. impl-detail::
+
+      getsets are attributes defined in extension modules via
+      :ctype:`PyGetSetDef` structures.  For Python implementations without such
+      types, this method will always return ``False``.
 
    .. versionadded:: 2.5
 
@@ -364,9 +366,11 @@
 
    Return true if the object is a member descriptor.
 
-   Member descriptors are attributes defined in extension modules via
-   ``PyMemberDef`` structures.  For Python implementations without such types,
-   this method will always return ``False``.
+   .. impl-detail::
+
+      Member descriptors are attributes defined in extension modules via
+      :ctype:`PyMemberDef` structures.  For Python implementations without such
+      types, this method will always return ``False``.
 
    .. versionadded:: 2.5
 
@@ -567,10 +571,12 @@
 
    Return the frame object for the caller's stack frame.
 
-   This function relies on Python stack frame support in the interpreter, which
-   isn't guaranteed to exist in all implementations of Python. If running in
-   an implementation without Python stack frame support this function returns
-   ``None``.
+   .. impl-detail::
+
+      This function relies on Python stack frame support in the interpreter,
+      which isn't guaranteed to exist in all implementations of Python.  If
+      running in an implementation without Python stack frame support this
+      function returns ``None``.
 
 
 .. function:: stack([context])
diff --git a/Doc/library/io.rst b/Doc/library/io.rst
index cf2f0bd..a72d3ed 100644
--- a/Doc/library/io.rst
+++ b/Doc/library/io.rst
@@ -96,8 +96,8 @@
 
    *buffering* is an optional integer used to set the buffering policy.  By
    default full buffering is on.  Pass 0 to switch buffering off (only allowed
-   in binary mode), 1 to set line buffering, and an integer > 1 for full
-   buffering.
+   in binary mode), 1 to set line buffering, and an integer > 1 to indicate the
+   size of the buffer.
 
    *encoding* is the name of the encoding used to decode or encode the file.
    This should only be used in text mode.  The default encoding is platform
diff --git a/Doc/library/mailbox.rst b/Doc/library/mailbox.rst
index 51cda8a..92f37cb 100644
--- a/Doc/library/mailbox.rst
+++ b/Doc/library/mailbox.rst
@@ -602,7 +602,7 @@
    `nmh - Message Handling System <http://www.nongnu.org/nmh/>`_
       Home page of :program:`nmh`, an updated version of the original :program:`mh`.
 
-   `MH & nmh: Email for Users & Programmers <http://www.ics.uci.edu/~mh/book/>`_
+   `MH & nmh: Email for Users & Programmers <http://rand-mh.sourceforge.net/book/>`_
       A GPL-licensed book on :program:`mh` and :program:`nmh`, with some information
       on the mailbox format.
 
diff --git a/Doc/library/math.rst b/Doc/library/math.rst
index 96ea91a..2f5e128 100644
--- a/Doc/library/math.rst
+++ b/Doc/library/math.rst
@@ -321,7 +321,7 @@
    The mathematical constant *e*.
 
 
-.. note::
+.. impl-detail::
 
    The :mod:`math` module consists mostly of thin wrappers around the platform C
    math library functions.  Behavior in exceptional cases is loosely specified
diff --git a/Doc/library/msilib.rst b/Doc/library/msilib.rst
index 7dc3632..7d64de3 100644
--- a/Doc/library/msilib.rst
+++ b/Doc/library/msilib.rst
@@ -396,10 +396,10 @@
 
 .. seealso::
 
-   `Directory Table <http://msdn.microsoft.com/library/en-us/msi/setup/directory_table.asp>`_
-   `File Table <http://msdn.microsoft.com/library/en-us/msi/setup/file_table.asp>`_
-   `Component Table <http://msdn.microsoft.com/library/en-us/msi/setup/component_table.asp>`_
-   `FeatureComponents Table <http://msdn.microsoft.com/library/en-us/msi/setup/featurecomponents_table.asp>`_
+   `Directory Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/directory_table.asp>`_
+   `File Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/file_table.asp>`_
+   `Component Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/component_table.asp>`_
+   `FeatureComponents Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/featurecomponents_table.asp>`_
 
 .. _features:
 
@@ -424,7 +424,7 @@
 
 .. seealso::
 
-   `Feature Table <http://msdn.microsoft.com/library/en-us/msi/setup/feature_table.asp>`_
+   `Feature Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/feature_table.asp>`_
 
 .. _msi-gui:
 
@@ -518,13 +518,13 @@
 
 .. seealso::
 
-   `Dialog Table <http://msdn.microsoft.com/library/en-us/msi/setup/dialog_table.asp>`_
-   `Control Table <http://msdn.microsoft.com/library/en-us/msi/setup/control_table.asp>`_
-   `Control Types <http://msdn.microsoft.com/library/en-us/msi/setup/controls.asp>`_
-   `ControlCondition Table <http://msdn.microsoft.com/library/en-us/msi/setup/controlcondition_table.asp>`_
-   `ControlEvent Table <http://msdn.microsoft.com/library/en-us/msi/setup/controlevent_table.asp>`_
-   `EventMapping Table <http://msdn.microsoft.com/library/en-us/msi/setup/eventmapping_table.asp>`_
-   `RadioButton Table <http://msdn.microsoft.com/library/en-us/msi/setup/radiobutton_table.asp>`_
+   `Dialog Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/dialog_table.asp>`_
+   `Control Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/control_table.asp>`_
+   `Control Types <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/controls.asp>`_
+   `ControlCondition Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/controlcondition_table.asp>`_
+   `ControlEvent Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/controlevent_table.asp>`_
+   `EventMapping Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/eventmapping_table.asp>`_
+   `RadioButton Table <http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/radiobutton_table.asp>`_
 
 .. _msi-tables:
 
@@ -553,5 +553,3 @@
 
    This module contains definitions for the UIText and ActionText tables, for the
    standard installer actions.
-
-
diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index 260b3b3..c8e47fc 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -1836,9 +1836,9 @@
 .. function:: system(command)
 
    Execute the command (a string) in a subshell.  This is implemented by calling
-   the Standard C function :cfunc:`system`, and has the same limitations.  Changes
-   to :data:`os.environ`, :data:`sys.stdin`, etc. are not reflected in the
-   environment of the executed command.
+   the Standard C function :cfunc:`system`, and has the same limitations.
+   Changes to :data:`sys.stdin`, etc. are not reflected in the environment of the
+   executed command.
 
    On Unix, the return value is the exit status of the process encoded in the
    format specified for :func:`wait`.  Note that POSIX does not specify the meaning
diff --git a/Doc/library/othergui.rst b/Doc/library/othergui.rst
index 9821173..d25645a 100644
--- a/Doc/library/othergui.rst
+++ b/Doc/library/othergui.rst
@@ -43,7 +43,7 @@
       `PythonCAD <http://www.pythoncad.org/>`_. An online `tutorial
       <http://www.pygtk.org/pygtk2tutorial/index.html>`_ is available.
 
-   `PyQt <http://www.riverbankcomputing.co.uk/pyqt/index.php>`_
+   `PyQt <http://www.riverbankcomputing.co.uk/software/pyqt/>`_
       PyQt is a :program:`sip`\ -wrapped binding to the Qt toolkit.  Qt is an
       extensive C++ GUI application development framework that is
       available for Unix, Windows and Mac OS X. :program:`sip` is a tool
diff --git a/Doc/library/platform.rst b/Doc/library/platform.rst
index 98b7972..b98d992 100644
--- a/Doc/library/platform.rst
+++ b/Doc/library/platform.rst
@@ -98,7 +98,7 @@
 .. function:: python_implementation()
 
    Returns a string identifying the Python implementation. Possible return values
-   are: 'CPython', 'IronPython', 'Jython'
+   are: 'CPython', 'IronPython', 'Jython'.
 
    .. versionadded:: 2.6
 
diff --git a/Doc/library/pty.rst b/Doc/library/pty.rst
index 6579ef0..be879f2 100644
--- a/Doc/library/pty.rst
+++ b/Doc/library/pty.rst
@@ -3,8 +3,8 @@
 ========================================
 
 .. module:: pty
-   :platform: IRIX, Linux
-   :synopsis: Pseudo-Terminal Handling for SGI and Linux.
+   :platform: Linux
+   :synopsis: Pseudo-Terminal Handling for Linux.
 .. moduleauthor:: Steen Lumholt
 .. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il>
 
@@ -14,8 +14,8 @@
 controlling terminal programmatically.
 
 Because pseudo-terminal handling is highly platform dependent, there is code to
-do it only for SGI and Linux. (The Linux code is supposed to work on other
-platforms, but hasn't been tested yet.)
+do it only for Linux. (The Linux code is supposed to work on other platforms,
+but hasn't been tested yet.)
 
 The :mod:`pty` module defines the following functions:
 
@@ -32,8 +32,8 @@
 .. function:: openpty()
 
    Open a new pseudo-terminal pair, using :func:`os.openpty` if possible, or
-   emulation code for SGI and generic Unix systems. Return a pair of file
-   descriptors ``(master, slave)``, for the master and the slave end, respectively.
+   emulation code for generic Unix systems. Return a pair of file descriptors
+   ``(master, slave)``, for the master and the slave end, respectively.
 
 
 .. function:: spawn(argv[, master_read[, stdin_read]])
diff --git a/Doc/library/signal.rst b/Doc/library/signal.rst
index a7cf33d..84f08b3 100644
--- a/Doc/library/signal.rst
+++ b/Doc/library/signal.rst
@@ -157,8 +157,8 @@
 
    The old values are returned as a tuple: (delay, interval).
 
-   Attempting to pass an invalid interval timer will cause a
-   :exc:`ItimerError`.
+   Attempting to pass an invalid interval timer will cause an
+   :exc:`ItimerError`.  Availability: Unix.
 
    .. versionadded:: 2.6
 
@@ -166,6 +166,7 @@
 .. function:: getitimer(which)
 
    Returns current value of a given interval timer specified by *which*.
+   Availability: Unix.
 
    .. versionadded:: 2.6
 
@@ -186,14 +187,14 @@
 
 .. function:: siginterrupt(signalnum, flag)
 
-   Change system call restart behaviour: if *flag* is :const:`False`, system calls
-   will be restarted when interrupted by signal *signalnum*, otherwise system calls will
-   be interrupted. Returns nothing. Availability: Unix (see the man page
-   :manpage:`siginterrupt(3)` for further information).
+   Change system call restart behaviour: if *flag* is :const:`False`, system
+   calls will be restarted when interrupted by signal *signalnum*, otherwise
+   system calls will be interrupted.  Returns nothing.  Availability: Unix (see
+   the man page :manpage:`siginterrupt(3)` for further information).
 
-   Note that installing a signal handler with :func:`signal` will reset the restart
-   behaviour to interruptible by implicitly calling :cfunc:`siginterrupt` with a true *flag*
-   value for the given signal.
+   Note that installing a signal handler with :func:`signal` will reset the
+   restart behaviour to interruptible by implicitly calling
+   :cfunc:`siginterrupt` with a true *flag* value for the given signal.
 
    .. versionadded:: 2.6
 
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
index 3666b92..0115fc1 100644
--- a/Doc/library/stdtypes.rst
+++ b/Doc/library/stdtypes.rst
@@ -195,9 +195,11 @@
 :meth:`__cmp__` method.  Refer to :ref:`customization`) for information on the
 use of this method to effect object comparisons.
 
-**Implementation note:** Objects of different types except numbers are ordered
-by their type names; objects of the same types that don't support proper
-comparison are ordered by their address.
+.. impl-detail::
+
+   Objects of different types except numbers are ordered by their type names;
+   objects of the same types that don't support proper comparison are ordered by
+   their address.
 
 .. index::
    operator: in
@@ -765,13 +767,15 @@
    If *k* is ``None``, it is treated like ``1``.
 
 (6)
-   If *s* and *t* are both strings, some Python implementations such as CPython can
-   usually perform an in-place optimization for assignments of the form ``s=s+t``
-   or ``s+=t``.  When applicable, this optimization makes quadratic run-time much
-   less likely.  This optimization is both version and implementation dependent.
-   For performance sensitive code, it is preferable to use the :meth:`str.join`
-   method which assures consistent linear concatenation performance across versions
-   and implementations.
+   .. impl-detail::
+
+      If *s* and *t* are both strings, some Python implementations such as
+      CPython can usually perform an in-place optimization for assignments of
+      the form ``s = s + t`` or ``s += t``.  When applicable, this optimization
+      makes quadratic run-time much less likely.  This optimization is both
+      version and implementation dependent.  For performance sensitive code, it
+      is preferable to use the :meth:`str.join` method which assures consistent
+      linear concatenation performance across versions and implementations.
 
    .. versionchanged:: 2.4
       Formerly, string concatenation never occurred in-place.
@@ -961,10 +965,11 @@
    For 8-bit strings, this method is locale-dependent.
 
 
-.. method:: str.join(seq)
+.. method:: str.join(iterable)
 
-   Return a string which is the concatenation of the strings in the sequence *seq*.
-   The separator between elements is the string providing this method.
+   Return a string which is the concatenation of the strings in the
+   :term:`iterable` *iterable*.  The separator between elements is the string
+   providing this method.
 
 
 .. method:: str.ljust(width[, fillchar])
@@ -1593,10 +1598,13 @@
    example, sort by department, then by salary grade).
 
 (10)
-   While a list is being sorted, the effect of attempting to mutate, or even
-   inspect, the list is undefined.  The C implementation of Python 2.3 and newer
-   makes the list appear empty for the duration, and raises :exc:`ValueError` if it
-   can detect that the list has been mutated during a sort.
+   .. impl-detail::
+
+      While a list is being sorted, the effect of attempting to mutate, or even
+      inspect, the list is undefined.  The C implementation of Python 2.3 and
+      newer makes the list appear empty for the duration, and raises
+      :exc:`ValueError` if it can detect that the list has been mutated during a
+      sort.
 
 
 .. _types-set:
@@ -1970,20 +1978,21 @@
 
       Return a copy of the dictionary's list of ``(key, value)`` pairs.
 
-      .. note::
+      .. impl-detail::
 
          Keys and values are listed in an arbitrary order which is non-random,
          varies across Python implementations, and depends on the dictionary's
-         history of insertions and deletions. If :meth:`items`, :meth:`keys`,
-         :meth:`values`, :meth:`iteritems`, :meth:`iterkeys`, and
-         :meth:`itervalues` are called with no intervening modifications to the
-         dictionary, the lists will directly correspond.  This allows the
-         creation of ``(value, key)`` pairs using :func:`zip`: ``pairs =
-         zip(d.values(), d.keys())``.  The same relationship holds for the
-         :meth:`iterkeys` and :meth:`itervalues` methods: ``pairs =
-         zip(d.itervalues(), d.iterkeys())`` provides the same value for
-         ``pairs``. Another way to create the same list is ``pairs = [(v, k) for
-         (k, v) in d.iteritems()]``.
+         history of insertions and deletions.
+
+      If :meth:`items`, :meth:`keys`, :meth:`values`, :meth:`iteritems`,
+      :meth:`iterkeys`, and :meth:`itervalues` are called with no intervening
+      modifications to the dictionary, the lists will directly correspond.  This
+      allows the creation of ``(value, key)`` pairs using :func:`zip`: ``pairs =
+      zip(d.values(), d.keys())``.  The same relationship holds for the
+      :meth:`iterkeys` and :meth:`itervalues` methods: ``pairs =
+      zip(d.itervalues(), d.iterkeys())`` provides the same value for
+      ``pairs``. Another way to create the same list is ``pairs = [(v, k) for
+      (k, v) in d.iteritems()]``.
 
    .. method:: iteritems()
 
diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index fd7a5c9..c7be131 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -417,8 +417,10 @@
    that is deeper than the call stack, :exc:`ValueError` is raised.  The default
    for *depth* is zero, returning the frame at the top of the call stack.
 
-   This function should be used for internal and specialized purposes only. It
-   is not guaranteed to exist in all implementations of Python.
+   .. impl-detail::
+
+      This function should be used for internal and specialized purposes only.
+      It is not guaranteed to exist in all implementations of Python.
 
 
 .. function:: getprofile()
@@ -440,12 +442,12 @@
 
    Get the trace function as set by :func:`settrace`.
 
-   .. note::
+   .. impl-detail::
 
       The :func:`gettrace` function is intended only for implementing debuggers,
-      profilers, coverage tools and the like. Its behavior is part of the
-      implementation platform, rather than part of the language definition,
-      and thus may not be available in all Python implementations.
+      profilers, coverage tools and the like.  Its behavior is part of the
+      implementation platform, rather than part of the language definition, and
+      thus may not be available in all Python implementations.
 
    .. versionadded:: 2.6
 
@@ -809,12 +811,12 @@
 
    For more information on code and frame objects, refer to :ref:`types`.
 
-   .. note::
+   .. impl-detail::
 
       The :func:`settrace` function is intended only for implementing debuggers,
-      profilers, coverage tools and the like. Its behavior is part of the
-      implementation platform, rather than part of the language definition, and thus
-      may not be available in all Python implementations.
+      profilers, coverage tools and the like.  Its behavior is part of the
+      implementation platform, rather than part of the language definition, and
+      thus may not be available in all Python implementations.
 
 
 .. function:: settscdump(on_flag)
diff --git a/Doc/library/types.rst b/Doc/library/types.rst
index 87fa0d5..637704b 100644
--- a/Doc/library/types.rst
+++ b/Doc/library/types.rst
@@ -241,8 +241,11 @@
    as ``datetime.timedelta.days``.  This type is used as descriptor for simple C
    data members which use standard conversion functions; it has the same purpose
    as the :class:`property` type, but for classes defined in extension modules.
-   In other implementations of Python, this type may be identical to
-   ``GetSetDescriptorType``.
+
+   .. impl-detail::
+
+      In other implementations of Python, this type may be identical to
+      ``GetSetDescriptorType``.
 
    .. versionadded:: 2.5
 
diff --git a/Doc/library/weakref.rst b/Doc/library/weakref.rst
index 5dcb030..d403c3c 100644
--- a/Doc/library/weakref.rst
+++ b/Doc/library/weakref.rst
@@ -1,4 +1,3 @@
-
 :mod:`weakref` --- Weak references
 ==================================
 
@@ -73,6 +72,11 @@
 
    obj = Dict(red=1, green=2, blue=3)   # this object is weak referenceable
 
+.. impl-detail::
+
+   Other built-in types such as :class:`tuple` and :class:`long` do not support
+   weak references even when subclassed.
+
 Extension types can easily be made to support weak references; see
 :ref:`weakref-support`.