I saw aesop rock mentioned early on for hip hop but noone said anything about El-P. not my fav as an MC (that goes to aesop rock) but as a producer he can't be beat. He just came out with a new album, I'll sleep when you're dead --it's like nothing ive heard in hip hop before. the one before that is fantastic damage and is excellent as well. he's a big fan of philip k. dick, a lot of his themes reflect that interest.
MCs i like are aesop rock (just an all out incredible poet with skill that makes it look easy), vast aire (hes got a very slow style, takes his time, i've heard interviews with him where he basically speaks like he raps) mr. lif (more old school style), cage (interesting poetry, spent some time in a mental institution, and raps about some hardcore shit), dizzee rascal (excellent battle MC, hes young and remarkably positive).
dj qbert is good, check out wavetwisters on dvd, and you will have no doubt how talented that guy is.
other groups:
the coup is awesome, also the perceptionists, company flow, dead prez... i like the definitive jux label; something to explore.
i like Q and not U. i also saw someone put down nomeansno. cheers. I'm not going to go into punk rock right now, i'm done tuckered out by all of the hip-hop excitement.
::whew::