I can see why some people want to change their names. Depends on how the databases are designed, but I think it should be possible to change usernames. It would make sense to make a piece of code that does all the stuff automatically, since if you are going to change one username, other people will want to have their names changed too. Letting people change their name by themselves would be a bit risky though, so a some kind of request system would be usefull. All this would probably take some time from the devs (in the short run and in the long run).
I am kind of on the fence on this issue. I don't mind the current situation, but I would probably change my username if it was possible.