When we started the Google Code project hosting service in 2006, the world of project hosting was limited. We were worried about reliability and stagnation, so we took action by giving the open source community another option to choose from. Since then, we’ve seen a wide variety of better project hosting services such as GitHub and Bitbucket bloom. Many projects moved away from Google Code to those other systems. To meet developers where they are, we ourselves migrated nearly a thousand of our own open source projects from Google Code to GitHub.
Wow. Also read the Wired article about GitHub.
I always preferred Git over anything else because it didn't force you into a a messy tree of trunk and branches and whatnot. GitHub I preferred because they are best at actually showing the code. On Google Code the code always was some clicks away, and then often hidden in the terrible SVN structure.
According to the wired article, Microsoft is also using Git. Torvalds got to be one of the most influential Software Engineers today, I guess the only other ones with similar reach are Language Designers like Stroup and van Rossum and compiler people like Stallman.