Since the question about how to do tagging with Django shows up quite often, I have written a small solution to this problem: AbstractTagging. This is a generic application and generic views that give you a very simple solution to add tagging to any model you have in your django apps. It's currently used by me in my CMS project. The source is in the stuff project.
It was a bit weird to build, because I had to dynamically construct a base class you can subclass in your models - this is because of the magic in django.core.meta, where model classes are turned into modules. But the result is quite nice, I think.
