[bosshog]

social networks focused on entertainment will have a limited shelf life, as the tend to focus on short term attention and on teens.

Linkedin is a slightly different case. It is like a useful business directory.

The next wave will be vertical SN's.(few billion dollar ideas there), and networks with a strong mobile component.

I have started to dump all my entertainment focused social networks. I keep an account on facebook, but only use it to keep track of people. I hate their stupid applications.