Hey,
Setting up a git repo holding all extensions hosted by WMF was one of the things on the git migration roadmap IIRC. AFAIK there is none yet - is this being worked on?
Right now it's rather hard to get an overview of all changes made everywhere and to do analytics on the overall codebase. You can of course write a script to work with all the different repos, but that's rather less convenient :)
Cheers
-- Jeroen De Dauw http://www.bn2vs.com Don't panic. Don't be evil. --