A major Python update has just been moved from the testing repositories and will be available on a mirror near you. The default "python" package is now for the 3.x series while the 2.x series has been moved to a "python2" package, with python-2.7 having been scheduled to be the last major release in the python-2.x series.
Since /usr/bin/python will now point to the 3.x binary, any program requiring 2.x needs to point to /usr/bin/python2 instead. All our packages have been updated accordingly, but any remaining issues found can be reported to the bug tracker (not the forums or mailing lists).
AUR and third-party packages/projects using Python will likely need updating to reflect this move, as many programs are still incompatible with Python 3.