GAE with Python setup.

I'm using mac snow leopard, by default the python version is 2.6. I've installed 2.7, but every time I start up the app, it complains: "You are using a Python runtime (2.6) that is older than the production runtime environment (2.7)"  I update the path in the GAE's preference but still doesn't work. Finally find the answer here:  http://code.google.com/p/google-appengine-mac-launcher/issues/detail?id=4
After pressing the enter, it works~

WARNING  2011-08-02 23:53:51,995 dev_appserver.py:4749] Could not initialize images API; you are likely missing the Python "PIL" module. ImportError: No module named _imaging

This is another small issue for mac user: install PIL module...
Found one good solution:  just run macport:  sudo port install py27-pil
You can run sudo port -y install py26-pil for dry run.