Yeah, and in some cases "big deal" == "legal requirement"

We've considered it for the research department I'm part of at a university. The nice part is that we all know and like github, but need to keep the repos private or on premise, depending on the grant. Further, a lot of research code is based on another project's code, and a git fork is so much nicer than mailing around tarballs, particularly after having had the task of taking a project, and trying to incorporate several teams' individual modifications back in into the core to base further research on it.