In not-so-recent news, Drupal migrated the drupal.org project repository from CVS to Git in late February, 2011. My experience with Git previous to this has been as a user fetching source code of x.org, mesa, dri, and other various Linux and Unix projects.
As a user, not a developer, I found the Git work flow confusing. I did not need to make local commits and it was hard to wrap my head around bringing in changes from multiple remote repositories.
As a PHP developer, I first grasped the work flow at Columbus GiveCamp 2010 when I needed to make a github account for the branch of the Audio module we hacked on. As well, some Ruby guy had a nice Git work flow diagram, which I promptly forgot all about until the not-so-recent event above.