The 37-year-old rapper, dancer and DJ, whose father Berry Gordy founded the Motown record label, played tennis as a junior and has attended some of the Grand Slam tournaments.

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Inside, a belly dancer performed live, and a DJ spun '80s and contemporary music while Yelp's 2, 000 guests--mostly folks in their 20s and 30s who are fans of the site--danced and ate finger food prepared by San Francisco restaurants.

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