21. KATY PERRY
It was the bi-curious kiss heard round the world — literally. The Santa Barbara native with the pastor parents and the pinup-girl looks hit No. 1 this year everywhere from Australia to Italy with her saucy same-sex anthem ''I Kissed a Girl.'' Now, with her second single, ''Hot N Cold,'' gone top five, and a nonstop international promotional schedule, she's scarcely got time to breathe, let alone smooch. Still, Perry, 24, says, ''I'm totally having fun! It's Hammer time.'' Pushed to name the best part, she points to ''the little moments'' like being spoofed on SNL — ''even though I think they could have made fun of me a lot harder.'' — Leah Greenblatt

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