If you look at the internals of the new CBS/NYT poll, the true effect of the debates becomes clear. It is manifestly not the case that they had the effect I thought they would have, which was to drive Bush's positives down, since he came across in such an unsteady way. Instead, it doesn't look like the debate influenced voters impressions of him at all. Instead, the debates did seem to have a very large impact on Kerry's positives, across a number of dimensions. This was a surprise to me because, while I think he did fine, he didn't seem to do anything particularly impressive. This suggests that in the next few debates it is more important that Kerry consolidate his new, higher positives. The question is how. It may be that the folks who talked to CBS/NYT were impressed that Kerry seemed much more authoritative and direct than the Bush barrage suggested he was. But it may be that Kerry looked good in comparison to Bush--so the shakier Bush is, the better Kerry looks in comparison.
This suggests a real question of strategy for Friday and beyond. One argument is that Kerry should stay "positive" and look presidential, and not try to draw blood from Bush. This may be misunderstanding what happened in the first debate. My sense is that Kerry was effective at needling the president, getting under his skin, but doing so in a way that didn't come across as a direct frontal attack on the president (that is, Bush got it but those watching at home didn't, at least not to anywhere near the same degree). This made Bush look bad and Kerry look good, by comparison. So the trick is to keep up this balance--negative enough to make Bush angry, but not so negative that it effects Kerry's newly buoyant positives.