Update #1 (5:59)
From ABC:
6 in 10 are female (SUSA had it at 55%, this is good for Clinton) , and "just under half" have a college degree (SUSA had this at 44%, this is good for Obama).
Update #2 (6:05)
From Time about 20% made up their mind in the last week, versus 30% in Ohio and an average of 31% in the Super Tuesday states. This isn't a surprise given the length of the campaign. About 30% where over 65, which represents a significant difference from SUSA's 22% (and good news for Clinton).
Update #3: (6:18) According to the National Review, Drudge has the exit poll reversed, and the right numbers are Obama 52, Clinton 47. And after citing those two sources in the same sentence, I now feel the need to remind ourselves to take all of this with a grain of salt.
Update #4 (6:29) : There is no way the National Review can be right: ABC has Clinton winning by 10 among white men.
Update #5 (6:42) : Via Markos, Mark Blumenthal at the National Journal notes that the 6:00 PM exit polls have consistently favored Obama by about 7 points more than the final result. The National Review post referenced above links to an analysis also suggesting about a 7 point bias for Obama.