SERVER-6226 adding note about find and modify change to the release notes

Author: Sam Kleinman

source/release-notes/2.2.txt

@@ -362,6 +362,21 @@ Documentation: :ref:`sharding-shard-key-indexes`
 Additional Improvements
 ~~~~~~~~~~~~~~~~~~~~~~~
 
+``findAndMondify`` Returns Null value for Upserts
+`````````````````````````````````````````````````
+
+In 2.2, for :term:`upsert` operations, :dbcommand:`findAndModify`
+commands will now return the  following output:
+
+.. code-block:: javascript
+
+   {'ok': 1.0, 'value': null}
+
+In the :program:`mongo` shell, :dbcommand:`findAndModify` operations
+running as upserts will only output a ``null` value.
+
+See: :issue:`SERVER-6226`.
+
 ``_id`` Index not Required for Updates to Capped Collections
 ````````````````````````````````````````````````````````````