As of this writing, we have more than 3 times as many articles as Math Wiki. I believe this makes us the largest mathematics wikia (18,836 articles).
The largest mathematics wiki on the Internet is probably PlanetMath, with 9,411 articles as of this writing. Another big one is AoPSWiki, with 4,806 articles.
I guess we're doing pretty good for a wiki about the most obscure field of mathematics ever :3 Oh, and most of the work is Ikosarakt's.