I think you're right to an extent. Unless these social sites adapt to where the internet is going which is a Web 2.5 era of online applications. Most of them are trying to implement this, Facebook and Myspace have, but they were not expecting the outcome of this. The virality and spamming usage for some of these applications is just a big turn off. A lot of people are already over the whole social networking phase and don't even bother logging into their accounts anymore.