Django: sqlite for dev, mysql for prod?
Use the same database in all environments.
As much as the ORM tries to abstract the differences between databases, there will always be certain features that behave differently based on the database.  Database portability is a complete myth.
Plus, it seems pretty insane to test and develop against code paths that you will never use in production, doesn't it?
Quick question: is it a good idea to use sqlite while developing a Django project, and use MySQL on the production server?