i would say its BoA. I mean, shes young so she still has time to make her as popular as ayumi is now, and we don't know how long ayumi's career will last. BuT ayumi is so much more talented than BoA....BoA can dance...but she cant sing...no offence. Utada's not much of a competition, but her new albums got her fans waiting for a LONG time so i think it'll do very well, althought it will be released in america.
