The Corporation for National Research Initiatives has released Python 1.6.1. This is a "bugfix" release for Python 1.6, fixing a GPL incompatibility in the license. The new 1.6.1 release can be found here:
There is great subtlety to GPL compatibility. I refer to the webpages of the Free Software Foundation for an explanation, in particular http://www.gnu.org/philosophy/license-list.html.
This change does not imply that Python 2.0 or later versions are now compatible with the GPL. Similar changes to their licenses need to be made there; these are still under negotiation. I'll keep you posted.
--Guido van Rossum (home page: http://www.python.org/~guido/)