Note: This may be dated, as it was created in 2008. However, there is a lot here that is interesting and useful.
Bring along your own version of Django rather than using the Google Development App Server’s version of Django, which is old.
Use code.google.com/p/google-app-engine-django to facilitate integration between the App Engine environment and Django. Provides tools to help development and administration, as well.
All Google App Engine applications run in UTC so use pytz to manage time within the application.
Hope you find this useful too!