When I’m not at my day job, I develop online communities. (Maybe, someday, that *will* be my day job). So, I’m constantly thinking and reading about what it takes to form, and sustain, and encourage community.
Community has to be developed. It doesn’t just happen. Certainly there are moments when a lot of people are in the right place at the right time (see smart mobs and Improv Everywhere) but it could hardly be called community.
However, community needs to be catalyzed in shared experience. And I’m willing to bet that the strongest communities want others to share in that same catalyzing experience. They might still have an us-them mentality, but they are more focused on bringing ‘them’ in than keeping ‘them’ out.