Eminem

It's been four years since we last heard from hip-hop's Real Slim Shady, a.k.a., Eminem. But according to 50 Cent, the man born Marshall Mathers is "working" on his long-awaited follow-up to 2004's Encore -- but there's just one problem: Mathers isn't satisfied with the new material.

While speaking to England's BBC Radio 1, Fifty -- who recently made an album announcement of his own -- hinted that Eminem's creative dissatisfaction might prevent the disc from seeing the light of day. "A lot of material he wrote prior to this is being scrapped," he stated. "He's got to feel like it's just happened, it's new and it's current. That's just how he is creatively as an artist."

They say patience is a virtue, and if the wait results in another record on the level of 2000's masterwork, The Marshall Mathers LP, we can't complain.