For the sake of conversation, let's just say that you could hypothetically change your username at any given time to anything you wanted.
Would you want to do it?
Personally, I like my name. It's a testament to one of my favorite childhood games, and I'm sure you've all played it.
-
I think I would keep mine. In fact i'm sure I would. I spent a long time trying to think of a username/gamertag that I like, and I plan on keeping it.