I'll be honest; I stink with names. I have trouble remembering them, and have to make a special effort to use them 3-4 times when I first meet someone, just to have a chance of someone's name sticking with me. I mean, I really have to work at it.
So, what are the chances that I'll remember your name if, say, I met you once 5 years ago at a conference, or worked in the same building as you for a couple of months 10 years ago.
Ah-yep. The odds aren't good. Unless you really made an impression (either good or bad) on me for some reason, or your name was unusually memorable, chances are, I'm going to be saying "John who? Ms. Smith what?" if you get in touch with me years later.
However... almost every social networking site lets you put up some sort of picture. And, you know, I have a much better memory for faces than names. Enough so that even a few years down the road, I'm easily able to recognize and place people I otherwise wouldn't remember.
So if you want people that you may not know too well - say, business contacts - to recognize and identify you, then please, please, please make it easy to do so. Put up a picture of yourself. It doesn't have to be funny, or artistic, or whatever - a simple passport photo, or a picture of you with a smile on your face, is more than enough to make the connection, and make the difference between "John who? Never heard of him.." and "Oh, yeah - John from the last TiE meeting! I remember him..."