Social networking nowadays is considered just a synonym for MySpace, Facebook, Twitter, etc.
And the Wikipedia link shown above is a classical example: you search for social networking, and you get social network service.
But it started before. And it is not limited to that.
During the Summer of 2009 I will start to release part of my research (few hundred pages, and few thousand pages of supporting references, links, articles, etc), on “cross-media convergence” in business