I'm not going to be able to do today's update justice, but let's touch upon a couple of themes quickly:
Firstly, Obama has been polling a couple of points ahead of our trendline for the past couple days. That could be noise, or it could be a sign that the race is turning a bit. Our model inherently behaves conservatively, and assumes the former until "proven" otherwise.
Secondly, Obama obviously got a very good number in Virginia today. That is not enough to turn the state into a toss-up all by itself; we still have Virginia as lean McCain. However, Virginia may well be a better path to 270 electoral votes for Obama than Ohio, where he got a not-so-good number from Suffolk.
Thirdly, someone polled Delaware! Our model (which knew nothing about Joe Biden) had previously seen Delaware as being about a 7-point race, so a +12 for Obama there suggests about a 5-point Biden bump. That's actually not bad as far as a VP candidate goes, but nothing compared to Sarah Palin.