I think she said something like "Ohhh, that would be pretty cool". Then the hosts asked who Ayumi was, and Utada told them she's a popular singer in Japan, who she thinks is really cute. She then said something about how they do really different stuff though, and people think they're rivals, but she said that they're really not. The hosts then drew comparisons between Ayumi and Utada, like how they both write their own music, and things like that. It's been a while since I had that file, so let me know if I messed anything up.
She handled the question pretty well I thought, it didn't seem like she got offended or anything like that.