If last October we got a bunch of MediaWiki developer stats thanks to the aggregation of data by Ohloh [1], now we are getting plenty more stats from Bitergia, including data from bug reporting and mailing lists:
http://blog.bitergia.com/2012/12/03/complete-basic-analysis-of-mediawiki/
Bitergia is a company based in Madrid formed by a small team of developers that have been working on FLOSS stats software for a long time. All the tools they develop are free software publicly available and open to contributions.
They have been kind enough to contribute some time and work setting up stats for the MediaWiki community. They also welcome feedback about the service and the data collected. I'm CCing Jesús M. González-Barahona, who has been my regular contact for this task in the past weeks.
Al good news for http://www.mediawiki.org/wiki/Community_Metrics !
[1] https://www.ohloh.net/orgs/wikimedia