Photo: Dowling/Getty

Twenty-four hours after his performance at the MTV Movie Awards, Eminem returned to the stage for a duet with Jay-Z at the launch party for DJ Hero, the latest interactive music game from the makers of the wildly successful Guitar Hero series. The two traded verses on “Renegade” (and swapped microphones relay-race-style when Em’s volume was turned down too low) and each treated the star-heavy Wiltern Theater crowd to half-hour sets of hip-hop hits.

Jay went on first, at quarter to midnight, and quickly rallied the room with classics like “99 Problems,” “H To The Izzo,” “Jigga What, Jigga Who?” “Dirt Off Your Shoulder,” “Encore” and “My President is Black,” which featured a montage of Election Day headlines and photos of Barack Obama, alongside iconic images of Martin Luther King, Jr. Em ran through tracks from his new album, Relapse, including “We Made You” and “3 A.M.” (on which he was joined by Travis Barker, who recently remixed the song), and closed out the night with “Lose Yourself.” On the visual end, Em’s set was more subdued, but what he lacked in flashy lights, the renegade rapper more than made up for in balls-out zeal.

And speaking of balls, while Eminem made no mention of his head-on collision with Sacha Baron Cohen’s Brüno character at the Movie Awards on Sunday night, the showstopper moment — which was today revealed to have been staged — was a popular topic on the red carpet. ”I would’ve been pissed,” offered Barker, who opened the show with a repeat of the TRV$DJ-AM sound-meets-vision Coachella set. “I think I’d be swinging at people if anyone’s ass came in my face.” But DJ AM added that, for all the brouhaha, Eminem was nothing short of a consummate pro at a run-through earlier in the day. “He was cool and beyond easy to work with,” he said. 

Barker’s Blink-182 bandmate Mark Hoppus, who arrived with Fall Out Boy’s Pete Wentz and told Rock Daily, “[We're] the new ‘it’ couple of the summer,” was among the scores of celebrities to attend the launch. Leonardo DiCaprio, Matthew McConaughey (with girlfriend Camila Alves), Christina Aguilera, Ryan Phillipe, Abbie Cornish, Amy Smart, Kelly Osbourne, Ashlee Simpson-Wentz, Kim Kardashian and Entourage’s Adrian Grenier, Jeremy Piven and Kevin Connolly were all spotted in a roped-off VIP area on the mezzanine. Philippe was especially animated during Eminem’s set, while DiCaprio and Connolly joke-jabbed each other, cheered and fist bumped from a few seats away.

But the biggest star in the room was undoubtedly the game itself, and AM, who was involved in the making — and mixing — of DJ Hero, hopes music enthusiasts will gain new appreciation for the turntable. “There are so many lame [people] popping up with an iPod and a playlist calling themselves DJs when they’re just a jukebox,” he said. “This game is incredibly realistic and you realize what it takes to mix two songs together. You actually have to do the work.”

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