The producer of the moment slices soul into tracks by J. Lo, Usher, and Amerie

Age 24

Mustworthiness The D.C. wunderkind has usurped the mantle of R&B’s producer of the moment (apologies to Kanye) by slicing and splicing soul into booty bumpers such as J. Lo’s ”Get Right,” Usher’s ”Take Your Hand,” and ”1 Thing” by protégée Amerie.

Uh-Oh Uh-Oh Uh-Oh, Yeah Harrison is also the genius behind 2003’s explosive ”Crazy in Love,” which featured Beyoncé with Jay-Z. But enough about the music — did he realize they were dating? ”I didn’t know what was going on. I just wrote a song about Beyoncé being in love.”

Past Perfect ”I definitely look to the past,” remarks Harrison, who has an admitted weakness for ’70s soul samples. ”But I always try to find something different.”

Next Cutting tracks on new CDs by Missy Elliott (out July 5) and Busta Rhymes (out in August). Plus: There’s talk of a reunion with Beyoncé and collaborations with Eve and Gwen Stefani.