[dharmaturtle]

> I also hate that the anki shared decks web site does not encourage collaboration...

Dude, I'm building exactly this. I'm not basing it on git for various reasons, but I am using event sourcing, and git is basically event sourcing for code. My system will (eventually) allow pull requests, comments, upvotes/downvotes, and all kinds of community shenanigans on flash cards. It's months away from release... but here's the repo if you wanna have a look: https://github.com/dharmaturtle/cardoverflow