Once Facebook launched its username program, there was a landrush when everyone decided to get either their name, or decided to steal somebody else’s – to the dismay on both you, since you could not get rid of it, and to the person you decided to steal it from.
But before now, after tons and tons of requests, Facebook has now introduced in its settings the option to change your username, meaning that you can regain/get rid of that username and gain another one. Only problem is, you only get to change it once, not twice if you screw it up again, but once.
Why did they do this, however, is a question for another day, since Facebook quietly launched this feature. Now go back and get your new name (again).