Eminem's 'Berzerk': A class by himself

Eminem's new single really is "Berzerk" (Aftermath).

Built around a sample of Billy Squier's "The Stroke," it's designed by producer Rick Rubin to call to mind hip-hop's golden age, complete with scratching and nods to the Beastie Boys.

Em pays tribute to those days, snapping, "Been Public Enemy since you thought PE was gym," before moving to more current ideas. "Berzerk" once again puts Eminem in a class all by himself, forcing hip-hop to question its sonic direction more definitively than even Kanye West. Shady's back. Back again!