And, for completeness, Chong Yidong, how co-maintained together with Stefan for quite a while (and did a great job as well). I think both of them were quite a big part of the "emacs renaissance" of the last few years.
And Stefan was a great maintainer. I was sad when I heard he was stepping down, but I can't think of a replacement that would make me happier than John.
http://emacs-fu.blogspot.fi/2009/08/interview-with-chong-yid...