Ask HN: Which repository system do you use and how?

I've been reading a lot lately about how each repository system works (especially Git) and was wondering what the predominant system is and how they use it?

Specifically, how they handle branching. It seems like at every place I've worked we've had a little different approach.

Also, do you use Gitstats or SVNStats like programs to have a loose idea of your output (not that lines of code is a good indicator of productivity in the least)?