GitHub's power comes from fork, pull request, and merge.
Adam Rifkin stashed this in GitHub
Klimt Finley speculates that the reason GitHub took a $100 million investment is to compete with Atlassian, which raised $60 million to compete with GitHub.
I love how Klint concludes the article:
The money may be in private and on-premise hosting, but the love is in the public repositories.
Perhaps most importantly, GitHub has become the Library of Alexandria for code examples. Since Git encourages granular recording of changes, programmers, be they absolute beginners or experts, can trace the steps of some of the greatest developers in the world and find out how they solved thorny problems. But if GitHub were ever to meet the same fate as the Library of Alexandria, it could be reconstructed from all those local forks distributed on so many developers laptops all over the world. Regardless of how this investment works out, that’s a hell of a legacy for the GitHub team to leave behind.
And I wonder if the fork-pull request-merge model is applicable to things other than code.