There've been rumblings about this coming for a while but it still seems to have crept up, and I didn't realise it'd be out before Christmas - end of November in fact.
The Black Keys (awesome modern heavy blues duo) are doing a rap album, and it's called Blakroc. If they weren't such arbiter's of good taste (Dangermouse produced their last album, and Dan Auerbach, one half of the Keys, released a great solo record this year), this could be a disaster, but the tracks that they're leaking sound quality. You can listen to Stay Off The Fuckin' Flowers (featuring Raekwon) here, and below is a rough video for a track with Mos Def and Jim Jones. A third track leaked too (again featuring Mos Def) but that's now gone. Anyway, the rest of it's sounding good, though it has the air of something that needs to be listened to as an album, rather than a bunch of singles thrown together.