Image is so important in the music industry these days. It's like it's ok to drool over fit people so long as you can pretend it's because of some other talent like their singing or something. It's crappy. Just look on top of the pops or whatever and you'll see that its rare for an ugly woman to be successful. I don't think there's much correlation between attractiveness and musical talent. Granted some mentally handicapped people (who presumably are less musical since musical abillity is masrginally related to mathematical abillity apparently) are generally less physically attractive but this can't explain the massively obvious trend. Lets face it, what really happens is that people who look like models decide to pursue a career in singing and some of them really can sing but mostly other people write songs for them that are designed to exploit their appearance and don't actually provoke any thought originating from above waist height!
What's any of that got to do with music? Bugger all.