README.md: add pointer to Google Cloud Libraries

Fixes #203.

Change-Id: I0faab2a8fa5c1725f8d45e4a93f6f1d98ff696d9
Reviewed-on: https://code-review.googlesource.com/12971
Reviewed-by: Ross Light <[email protected]>

Author: jba

README.md

@@ -8,6 +8,14 @@ These are auto-generated Go libraries from the Google Discovery Service's JSON d
 Due to the auto-generated nature of this collection of libraries, complete APIs or specific versions can appear or go away without notice.
 As a result, you should always locally vendor any API(s) that your code relies upon.
 
+If you're working with Google Cloud Platform APIs such as Datastore or Pub/Sub,
+consider using the
+[Cloud Client Libraries for Go](https://github.com/GoogleCloudPlatform/google-cloud-go)
+instead. These are the new and
+idiomatic Go libraries targeted specifically at Google Cloud Platform Services.
+
+
+
 Announcement email:
 
 * http://groups.google.com/group/golang-nuts/browse_thread/thread/6c7281450be9a21e