Totally agree about Celine Dion -- for me, a splendiforous example of no "there" there.
But there are, of course, popular singers who I catch here and there in a particular context who are just fine. When the whole world was going on and on about Adele being chosen to do the title song for SKYFALL, I had no idea who that was. I'd never heard the name. And that's not meant to be derogatory at all. I just don't follow that world.