Today we released version 1.3.3 of the App Engine SDK for both Java and Python. This is a minor release that includes changes and a few issue fixes for the datastore, administration console, and when deploying applications. For more information on all the changes, please read the 1.3.3 release notes for Java and Python.
Additionally, the Python SDK has a new experimental feature that gives you the option to use SQLite as the datastore stub backend. Using SQLite within the dev_appserver should speed up performance of your local datastore when testing on large datasets. (Note that this feature does not add SQL support to the App Engine SDK or service.) If you try out this feature, please give us your feedback on the App Engine Python users group.