Not only has GNOME decided to switch to using git. We have learned that development at Microsoft is based on git too.
Development for Windows 7 is handled on a modified (in-house) version of git that allows it to run natively on Windows (the blessings of the GPL, I believe they must think at Redmond). Why reinvent the wheel when one of the best tools for the job is out there for free?
According to our sources, at first, some developers introduced git behind the backs of their managers by using it on top of cygwin. As they felt more comfortable with the tool and presented their benchmarks to management, it was obvious that git allowed development to be carried out in a much more efficient fashion. Then they started the process of making git run natively on windows without needing an intermediate layer, which allowed it to run even faster. It has been reported that the patches to git will be sent upstream once Windows 7 reaches RTM.
This may sound as shocking news for some people, but over the last couple of years Microsoft has been trying to get cozier with open source... and this is yet another example of it. Unfortunately Microsoft's Horacio Gutierrez wasn't available for comments, nor Lawrence Crumpton.
Having said that, did you notice that it's April 1st? It's the only way something that far fetched could ever be published.
My opinion: I hope they are using RCS... or even better: no source control at all. :-)