There wasn't a demand for Git repos any more than there was a demand for Hg repos. For instance, open source projects moving away from SVN seemed to be pretty

There wasn't a demand for Git repos any more than there was a demand for Hg repos. For instance, open source projects moving away from SVN seemed to be pretty evenly distributed between Git and Hg. The real demand was for a way to publish code and collaborate, and GitHub provided a truly innovative approach (the social aspects, encouraging forking and pull requests) that was miles better than the alternatives (SourceForge was already in decline, Google Code didn't have the social/forking/pull request aspects). I think they would have been successful with any distributed VCS. I always preferred Git, so I'm happy they chose Git, but I think that if they had chosen Hg, we'd be talking about how Hg won the popularity war instead of Git.