Why? I really don't see the purpose of a federation of git repos. Git is already totally decentralized. 99% of projects only have a small list of committers. Tangled just doesn't solve an actual problem. Github was used because it was an easy to set up, free, place to store code and share it, and it had source viewing which was a step up from sourceforge. With multiple solutions available that makes this easy, its just not necessary to federate anything. The common user account part of github just isn't critical.