I like Tim Parkin's design here: http://psf.pollenation.net/cgi-bin/trac.cgi/attachment/wiki/HomePage/tparkin/python-hompage-ideas-export.png
I'd make the following changes:
1. Replace rightmost column (NASA, Quote, Using Python) with News and Announcements
2. Move 'Using Python For' in the center column (where News and Announcements is)
3. Move Quote and NASA in the leftmost column (below the links). These are 'out in the open' (i.e. no boxes).
Reasoning: News and Announcements shows the activity and we shouldn't have to scroll for it.