Well I don't know that much about Ayumi Hamasaki. So I can't really say anything about her. I think both singers are very pretty and have sweet voices, but I'm still more of a Utada fan. Someone told me it wasn't really Ayumi that Utada sort of has a rivalry with in the Jpop world, but a singer named BoA. I'm not familiar with alot of Jpop music, so I wouldn't touch on that subject. But from looking at the pics, tombraiderjmm posted, they look like friends.