You can use this cache backend to cache data in-process and avoid the overhead of pickling. Make absolutely sure you don't modify any data you've stored to or retrieved from the cache. Make deep copies instead if necessary.
The backend is basically identical to Django's stock locmem cache (as of r15852 - after 1.3rc1) with pickling removed. It has been tested with that specific Django revision, so basically it's >=1.3 compatible.
See Django ticket #6124 for some background information.