I struggled through about half the 2006 Alaska gubernatorial debate that ran last night on C-SPAN before losing patience with it. My quickie take is the Palin is going to be a tough opponent. She was pithy, stayed exceedingly vague, and was very disciplined about sticking to her talking points (even when they had little to do with the question). She also came off as fresh and charming. I'd guess she'll follow the same strategy during the VP debate, which should play pretty well. I can see Biden demonstrating a pretty detailed grasp of the issues while Palin gives a lot of two-sentence answers, but with a few memorable quips thrown in. The cable pundits will almost certainly declare her the winner if that's the case.
My favorite moment from the 2006 debate: The moderators asked the candidates where else in Alaska they'd live if they had to move. (Most of the debate questions were either extremely parochial or asinine like this one.) Palin misunderstood the question, going on about why she loved the Mat-Su Valley, where she currently lives. Finally, the moderator, trying to charitable, said, "So ... you'd just move to Palmer or some other place in the Valley?" The audience laughed, at which point Palin sensed an opportunity. She responded with: "Well, laugh if you will, but that is my answer, yes. The Valley is large. You know, the burrough is the size of West Virginia, it's huge. There are plenty of places in there to choose from." I have a feeling it won her a few votes.
(I'll watch my recording tonight and update with exact quotes.)
Update: I see that Time's Karen Tumulty flagged this question before I did.
Update II: Item now reflects the precise exchange.