Re: Promoting a Social Network. Discuss.
The way you compete with an established player is to offer content (and not just functionality) that they don’t have. You and I might agree that Ning is lacking, but it’s good enough for a lot of people to stick around, so it might be worth pitching the site in a different way other than focusing on the “whiz-bang.”
With a narrowly-focused subject like yours, it might be better to directly engage with groups active in that topic/space. Since your site has an academic bent, it would be good to talk with programs and/or publications that serve that audience, including subject-specific blogs that you can potentially cross-promote with (have you tried pitching to the editors of gaming sites?). Don’t be afraid to “cold call.” 
My current side project (http://readwritepoem.org) has an academic component too and so far we’ve only communicated that we relaunched the site as an “online magazine / social network” (sometimes specificity is lost on people, so don’t bother mention BP immediately) to a few key folks and we now have a number of interviews lined up with journals and an academic publication (we got that one through a generous Twitter contact). We’re hoping that’ll steamroll into more publicity which should help fuel the viral buzz.
