A few interesting tidbits from the Register poll I haven't seen anyone else discuss:
Most surprising of all to me was that Obama held a one-point lead among union households. This defies all conventional wisdom, as Clinton and Edwards have gotten most of the major union endorsements (Dodd got the big Firefighters support), and Obama is not thought to appeal as well to working-class voters as some.
A friend of mine said that a union endorsement doesn't mean rank-and-file support, but still, this is a startling number. It's either great news for Obama, or evidence that the overall results are off.
Clinton may have a big lead nationally on the question of electability with Democrats, but she leads Obama by three points here. That's big, because it takes away a big fall-back decision point for voters who decide at the last minute. The other fall-back, her experience, is a good one to have, but Iowa polling has consistently shown that Democrats prefer change to experience.
Something else: One would think that last is true even more for Independents and Republicans, especially the latter. Why would Republicans change their registration to Democratic if they didn't want big change?