Be robust in what you accept, which might be a JSON object w/o an outer wrapper 'data' object.
diff --git a/apiclient/discovery.py b/apiclient/discovery.py
index a5b7c9a..fe98db1 100644
--- a/apiclient/discovery.py
+++ b/apiclient/discovery.py
@@ -111,7 +111,10 @@
       if resp.status == 204:
         # A 204: No Content response should be treated differently to all the other success states
         return simplejson.loads('{}')
-      return simplejson.loads(content)['data']
+      body = simplejson.loads(content)
+      if isinstance(body, dict) and 'data' in body:
+        body = body['data']
+      return body
     else:
       logging.debug('Content from bad request was: %s' % content)
       if resp.get('content-type', '').startswith('application/json'):