Mrs. XXX-tina Aguilera.
I love this girl. She's changed so much over the years, both vocally and stylistically (is that even a word? - she can make pregnancy sexy!), yet legions of fans adore her every move. I have to admit that I haven't always been a fan, but her music is catchy and makes me dance. What more can I ask for?
Oh, and her music? Keeps gettin' better.