The people I have on instant messaging programs are people I already know. I don't feel the need or want to see/talk to them when I'm online because I mainly use the internet for meeting new people. I talk to my friends on the phone mostly.
IRC can be used as a way of speaking to people you don't know.
Maybe it's the channels I am often in, but most people I meet on IRC are more interested in privacy than in displaying their face for unknown people to see. Displaying your face to friends is one thing... to strangers is less desirable for many people. The whole a/s/l thing was popular for quite awhile once you started seeing AOL and IM stuff going around. It isn't anymore because people don't want to share that information. Privacy is becoming more and more of an issue with people (at least from my experience). That said, I don't frequent the #chat or #cafe channels or similar ones that are meant for trying to meet people. Of course, what percentage of IRC users do? (That's rhetorical as I'm sure no one has that data, but I'm sure it's a low number).
