I'll admit I'm crazyily addicted to LinkedIn.com.
It's not that I love social networking as mySpace didn't do much for me and my page there is languishing greatly. I've been on classmates.com since at least 2001. Classmates could have been really cool but they didn't expand beyond their school focus fast enough - plus they charged for basic functionality.
I think LinkedIn is a great way to keep in contact with people from various facets of life (eg. work, school, friends, others). I've gotten back in touch with so many cool people as a result of LinkedIn. Now, if my LinkedIn contacts maintain their profiles I won't end up loosing track of people again.
I have been like a relentless pusher getting everyone I know and people I barely know (2 years ago) on it. But I really think this site is great.
The potential for recruiting and finding vendors is pretty cool. As a Website Producer, I often need to find service providers and freelancers and it's much easier to find and be assured of quality when working with people that have worked for people I know. This site facilitates this process. (I don't like it though when people add contacts that they don't know though - this undermines this feature of the site.)
Great site for people looking for jobs too. Before considering a job you can check with your contacts and your contacts' contacts and it's possible you'll be conected to someone already at the company, so you can do some background checks before making a big jump.
There's more on the site too. I''m still spending way too much time on the site figuring it out.
I have joined the Linked Innovators group. I'm trying to figure out how to do some cool things on and with the site. I'm dying to figure out what the Forbes group is.
Just when I was really getting to love the site I read an article (I don't have the link right now - if I find it I'll edit this and put it in - but let's be honest I'm the only one reading this) about how nefarious people are stealing indenties, phishing and targetting viruses to users of these sites.
Way to put a damper on a party just getting going strong.