Zope seemed to have great people behind it, and was very solidly built, but it seemed a lot more monolithic, which ended up polarizing people.

Django really benefits from the ability to swap out everything. People who hate the default libraries just find something better to use.

No migration? Use South. Some people run Django on Twisted or Tornado. There are different template libraries that people use. I'm not sure if the model layer can be swapped out so easily (without messing around with custom user authorization), but there's nothing to stop people using django models for authorization, and a separate database interface (even a no-sql one) for other data.