Python 2.5 ships with simplejson, and in Python 2.6 it's been renamed to plain old json. I'm not sure on the implementation - one of the problems with Python JSON implementations was fragmentation, so if you wanted the standard implementation you'd use simplejson, but if you wanted the fast one you'd use cjson, yet if you wanted the maximally compatible library there was yet another 3rd-party JSON library. I'd like to think that the json module is fast and standards compliant, but I haven't looked at it.

I kinda would like type hinting too, although that's a deeply divisive issue in a dynamic language community.