Social networking like Facebook.com is more than just fun. It's a way to meet new friends who share your interests. You form a community with people you would never have had a chance to meet because this is the internet, after all.
What I get a kick of, is how some people use FB. Instead of discussing a topic or introducing one, they give you a run on commentary on their activites: "I'm sitting in traffic listening to the radio while I'm texting to my FB account on my Blackberry." I don't think that's what FB is for. Yeah, people do use it for that but I see that fading out. More and more you'll see people put in something that interests them. Then we can comment on it and maybe a discussion will ensue.
I've also just joined "eons.com" but haven't gotten on yet. I have to wait for confirmation. Eons.com is for boomers, old farts like me. It doesn't look like that much fun, but wait till I get on.