Today's Confused Query

For some reason, I'm receiving a sudden flurry this week of invitations to join this thing called LinkedIn that I don't really understand. Nor do I understand why, after getting one or two requests per month over the last year, I have about forty in the last six days. Friends, acquaintances and a few utter strangers write, "I'd like to add you to my professional network"…but these people can write to me any time they like and many of them are already sending me little e-mail newsletters about what they're up to, professionally speaking. What is going to happen after I join their "professional networks" that can't happen if I don't?

I've accepted some invites and I've browsed the LinkedIn site and I still don't have the foggiest. I'm not looking for a position as a Linux Systems Operator and there's absolutely no one who went to college with me I yearn to contact again. Matter of fact, I'd gleefully subscribe to a service that guaranteed I'd never encounter some of those people again.

What am I missing here?