Dalin pointed me to this bad-ass blog post about how Mozilla does metrics around community management: http://eaves.ca/2011/04/07/developing-community-management-metrics-and-t...
Check this dashboard out!
I think something like this could be totally awesome for figuring out how we're doing in terms of onboarding new contributors, retaining existing contribitors, and gauging the overall "health" of the community.
Anyone have any other pointers to cool stuff projects are doing to make sure their contributors are healthy and happy?