I'm sorry, but there's no need for universities to have a social network, it doesn't add any benefict to its users, and it would be yet another (bunch of) useless social network(s).

Why should universities adhere to this? Just because Web 2.0 is hyped? Come on...

A good prespective of what I think about it was written in Portuguese by Paula, <a href="http://blog.felisberto.net/2007/10/10/universities-do-not-join-web-20-please/">here</a>.