DOCS-929 upgrade procedure edits

Author: Sam Kleinman

source/release-notes/2.4-upgrade.txt

@@ -45,7 +45,7 @@ procedure.
    after stopping version 2.0 :program:`mongos` processes to confirm
    that none are still active.
 
-#. Start a single versions 2.4 :program:`mongos` process with
+#. Start a single 2.4 :program:`mongos` process with
    :setting:`configdb` pointing to the sharded cluster's :ref:`config
    servers <sharding-config-server>` and with the :option:`--upgrade
    <mongos --upgrade>` option. You can upgrade an existing
@@ -88,9 +88,13 @@ procedure.
    option.
 
 Once you have upgraded, *do not* introduce version 2.0 MongoDB
-processes back into the sharded cluster. This can introduce in
-metadata problems. This metadata change and the upgrade mechanism will
-help prevent errors caused by cross-version incompatibilities.
+processes into the sharded cluster. This can introduce in
+metadata problems. 
+
+.. is the following true? 
+
+   This metadata change and the upgrade mechanism will help prevent
+   errors caused by cross-version incompatibilities.
 
 .. _upgrade-cluster-resync:
 
@@ -104,7 +108,8 @@ modifying data. If this occurs, the :ref:`config servers
 <sharding-config-server>` must be re-synced, and there may be problems
 starting new :program:`mongos` processes. The :term:`sharded cluster`
 will remain accessible, but avoid all cluster metadata changes until
-you resync the config servers. 
+you resync the config servers. Operations that change metadata include:
+adding shards, dropping databases, and dropping collections.
 
 To resync the config servers:
 
@@ -120,8 +125,8 @@ To resync the config servers:
    ensures that most :program:`mongos` instances will have
    uninterrupted access to cluster metadata.
 
-#. :program:`Mongodump <mongodump>` the data files of the active
-   config server (``configA``).
+#. :program:`mongodump` the data files of the active config server
+   (``configA``).
 
 #. Move the data files of the deactivated config servers (``configB`` and ``configC``)
    to a backup location.

source/release-notes/2.4.txt

@@ -37,6 +37,11 @@ process.
 
 .. _`downloads page`: http://www.mongodb.org/downloads
 
+Upgrade Process
+---------------
+
+See :doc:`/release-notes/2.4-upgrade` for full upgrade instructions.
+
 Changes
 -------