Add support for prefetching fields This makes it possible to specify the fields that should be prefetched as part of a getForFields query. Doing a prefetch on a ReferenceProperty when it is known that the property will be referenced in (almost all) entities is far more efficient than doing the invididual fetches sequentially.

A list of bugs is available in the Google App Engine SDK project on Google Code.

The issue tracker is at http://code.google.com/p/googleappengine/issues/.