ESTELLE
Her U.S. debut, Shine, features collaborations with everyone from Mark Ronson to will.i.am. Her Kanye West duet, ''American Boy,'' has notched more than 1.4 million digital sales. And she recently held it down as the only woman on tour with Gym Class Heroes and the Roots. So how does the British soul siren, 28, look back at 2008? ''I'll remember it for never being in my house,'' she jokes. But that's not a complaint. ''It took me four friggin' years to get this s--- out. I can't be mad at anything right now.''