I just found out about Python Koans by Greg Malcolm (thanks dude) after listening to the from python import podcast podcast (which I find amusing, thanks guys).
It's an awesome way to learn Python. Instead of just reading tutorials and/or books you learn Python by coding.
The interactive tutorial is built around unit-tests and you advance and gain new skills by passing tests and it's really funny. You do learn a lot about the Python language when doing the Koans so I recommend it even if you've been using Python for a while.
Another cool thing is that you learn how to do unit testing in Python, if you're not already familiar with it.