GitHub has released contributions (summary of Pull Requests, closed issues and commits).
This is the count of contributions to public repos at GitHub.com from Wed, 11 Jan 2012 01:52:32 GMT till Fri, 11 Jan 2013 01:52:32 GMT.
To repeat:
- Take the first 1000 users in GitHub according to the count of followers.
- Sort them by number of public contributions.