So I am going to go ahead and throw this one out. It is by no means complete.
It requires PyObjC. You need to put the nib file in the matplotlib data path. On panther you can run a script with -dCocoaAgg and resize the native window. Unfortunately tiger changed something with creating an imagerep and things aren't working quite right with it yet.
You DO NOT have to use pythonw to run your scripts.
There a lot of things I would like to do with this including using QTKit to dump a movie and adding clipboard support. Long term, it would be nice to make the plots embeddable in an app. Anyway, let me know if anyone is interested in working on this.