My extended comment on the definition of "social networking" over at Warlick's
Here's the thing: if you define "social networking" too generally, it won't really mean anything. You not only end up including not only IM, email and BBS's, but the Kiwanis Club, football team, people who sit with you at lunch in the cafeteria, family, etc. Social networking writ large is central to the human experience and always has been. The study of this stuff is certainly worthwhile, but it has a name already: sociology.
What is new here? What has changed to bring "social networking" to the fore as a subject for discussion (and investment)? What is new is that people, kids especially, have technology and social practices to explicitly create and publish an individual statement of their social network -- their friends. We didn't do that before. The closest we'd get is the invitation list to a birthday party or who we gave Valentine's Day cards to. That innovation (with a few tweaks for easy group formation and adding things that aren't people to your social network) is central to the popularity of MySpace and Facebook.
That is what has changed and why people are talking about "social networks." If you don't understand that, you don't understand the phenomenon.