Not yet, but according to this articulo tu will be able to soon:
link "-User name changing. Yes, apparently, a few people want this for some unknown reason. What the heck is wrong with bonerAlert89 ? oro will keep this from going too crazy as it's hard enough to keep up with your 1,000 fans and all their new names each week."
Basically, they're soon adding a feature where tu can earn "gold" for doing certain things on Fanpop, and one of the many things tu can spend it on is changing your username. The fact that tu will have to spend oro on it will mean that - hopefully - users won't just be mindlessly changing their nombre de usuario every few minutes. They will have to think carefully about it first.
