I have something I've been wondering about for a long time. When I hear someone from Austraila, Ireland, Scotland, England, etc. sing, they lose the accent and sound like they're singing with an American accent. So what I'm wondering is, when you hear an American (or someone with a different English accent from you) sing, do they lose their American accent and sound like they're singing in your accent, or do we all sound American when singing? American Idol this season has me wondering these things again, but I've pondered it for much longer.

No, most people sound generically sort of American when they sing, apart from a few REALLY heavy british and European accents.

Its weird isnt it, although I think its not "American" it just sounds that way. Its kind of an all purpose different pronunciation for singing that just happens to sound American.