In that way, I dont have to download a huge 500MB file for each upload as git sends diff deltas of the data blocks.
Last time I checked, they were working on getting the client updater ported over to Linux so it could update the same way it does on Windows. I think that would probably be the best they could focus their time on, rather than setting up a git server for the small number of PA players that know how to use git.
Actually, as much as I like Git, it's not at all suitable for hosting large binaries (because a clone would download the complete history). SVN would be more suited for that kind of task.