Just my guess, but I bet that from this point on, few people (in the developed world) will race to sign up for a new social network. Why? Given the societal and personal costs (and benefits) that we've seen with previous social networks, a lot of lay people are re-evaluating the utility that such services provide them. In many cases, the answer is to keep your current social network, but increasingly disengage from i…
At this point, I'd like to preserve that network of friends independent of facebook and most of those folks feel similarly. In that sense, there is at least some demand for a social network that isn't evil.