A lot of people tend to just CHANGE their screennames whimsically.
This is bad-for-business. Sometimes, I'm trying to work out a deck idea and I have very little time to be on and test that day. So, I start searching for any familiar names that I can find and get a couple of games in. (sometimes, you just need to make sure you can get an opponent that's not random and get some good games in)
Then, when you get three responses from "GAME?," you don't choose the two unfamiliar (changed) names and they're all like "you don't want to play me anymore?"
If everyone kept ONE name and stuck to it, we'd get a better flow going...