Metamoderation has always demonstrated the ability to support quality, especially in the absence of identity. People lacking history or demonstrating poor behavior punish themselves and self-select in that environment.
I'm not complaining except for the fact that I'm deliberately avoiding Facebook - there are people on there I want nothing to do with and from whom I wish to isolate myself, and the utter complexity of privacy issues on Facebook further turn me off to it. I feel safer when I can dissociate my accounts across various sites, however misguided that may be. I'd like to participate on your site, as it looks interesting, but the requirement of a Facebook account is a complete dealbreaker.
What do you use for search?
Don't you want to try hosted search like IndexDen (IndexTank alternative) and move search management to our shoulders?
BTW: We're helping everyone with integration ;-)
Kind Regards http://IndexDen.com
Also inevitably you'd need some grouping/labeling so users can filter out/in. E.g. I'd never want any submission about cats.