This is something for people with free time - probably students or people in the 10-25 segment. Still it can be fun to do it once in a while, I know I've done a few times. The commercial part shouldn't be neglected given the level of social interaction - I find it similar to the ringtone craze, though it's not the same thing. And since I mentioned the IM business side, read Bill's take on IM data transfer.