It seems that bloggers like to make predictions about the outcome of future events. If you're "right" you get to brag, if you're "wrong" you get to frame your post-event commentary around your earlier comments (something along the lines of "these factors made X happen even though I predicted Y:"). So, even though I'm not a "real" blogger I'm going to amuse myself by jotting down some thoughts.
Many seem to think Bush will be more aggressive tonight. Since he can't defend his own record he'll go after Kerry's with everything he's got. There's something to that. In Bush's mind Kerry is a despicable and immoral flip-flopper and he needs to be exposed as such.
On the other hand, the town hall format means that winning the sympathy of the audience will be important. No doubt Bush's famous social skills will alert him if the crowd is not responding well to his attacks, causing him to tone it down. I fully expect him to be joking a lot, perhaps adapting a tone of self-mockery at times, something he does really well.
As for Bush and substance, Sullivan today pointed out that conservative magazines like National Review and The Weekly Standard are starting to acknowledge the grim realities in Iraq (as this cover shows). This could mean the Bushies now realize the dangers of seeming hopelessly "out of touch". If so we may see a similar change in Bush tonight.
Apparently Karen Hughes has briefed Bush extensively on his defensively aggressive posturing, so I expect him to control himself better this time. Watch for a lot of smiling (of varying authenticity). He won't avoid playing defence completely though. Nobody can when you've been shielded from reality by yes-men while you retain a near-religious conviction that you are "right" and your opponent is "wrong".
How defensive Bush seems will probably end up being the most important factor in the whole debate. Will Kerry manage to attack without alienating the audience? Will Bush feel that he has the support of the audience so that he can shrug off attacks and hard questions from the audience? My guess: He'll be better than in the first debate but not well enough to "win" this debate.
As for Kerry I suspect he'll look much like he did in the first debate. For his sake I hope he thinks on his feet and answers the questions on the fly instead of relying on scripted responses. He should appear even more confident and controlled, which is basically what helped him gain over 5% last time. He may even show signs of too much confidence. There is a slight chance he will attack far more forcefully (many Dem pundits have been calling on him to "finish Bush off"), but if he's smart he won't risk it. As Clinton said, you must show "respect for the office". There is only one good reason to attack feverishly and that is if Bush shows no signs of insecurity or irritation and he needs to "tipped over the edge".
That's pretty much it. Kerry will do more of the same. Bush will a) work the audience well (joke with people who ask questions, etc) and b) avoid becoming as irritated. Past readers will recall I judged the first two debates +5 for Kerry and +1 for Edwards. This one will be a +3 for Kerry.
Oh and while I'm at it: If my prediction is right (Kerry win by +3 or more) I also think Kerry will win the election on Nov. 2. Unless Bush captures Bin Laden at the last minute of course.... :)