Which is ur favorite social network and why?

I`m a StartupNation.com fan.

err ofcourse besides startupnation

1. I depends on the purpose. Of the list you presented LinkedIn targets a
more professional group. It is not exactly a social network as they tend
not to focus on community discussions, etc.

2. The audience might matter. My son would likely prefer something
other than LinkedIn. His friends are more likely on Facebook.

SuN is a community but more like a forum and a resource that is shared.
LinkedIn is more for directed requests and to see who knows someone at
a particular company (chain of connections).

Beta tester for LinkedIn. Much more recent member of SuN.

John Corey