The summary: "First, git's Windows support is the weakest out of the three DVCSs being considered which is unacceptable as Python needs to support development on any platform it runs on. Since Python runs on Windows and some people do develop on the platform it needs solid support. And while git's support is improving, as of this moment it is the weakest by a large enough margin to warrant considering it a problem.
Second, and just as important as the first issue, is that the Python core developers liked git the least out of the three DVCS options by a wide margin."
I'm using Mercurial for the same reason - Windows support without complex dependencies.