What to Watch For: Biden
1. He's solid: Biden is actually a pretty good debater. In 2008, he was essentially coached just not to screw up, with the thought being that there was no way his debate against Sarah Palin could be a positive given the extraordinarily low expectations. Moreover, the expectations for Biden are quite low, as Republicans and satirical news outlets like The Onion make Biden a routine target of jokes and ridicule. The expectations game is poisonous for democracy, but I expect it to serve Biden well this time around.
2. Foreign policy: Did you watch the Democratic primary debates in 2008? Biden was really, really good on major fopo questions. Shockingly so. Ryan, on the other hand, hangs his hat on domestic policy issues related to tax and finance policy. Foreign policy is not one of his strengths. That said, what might normally be "Advantage: Biden" may be nulled as the Obama administration is coming off a tough few days of Libya in the news cycle. If Biden can come up with the administration's salesworthy explanation of why information has been slow to seep out (and I suspect there is one, what with the not wanting to compromise an ongoing terrorist investigation) then its a win, but if Ryan can pounce with some Libya lines, its a danger spot.
3. "Ordinary People" (not the Oscar winning film): Biden's got his blue-collar Scranton-man schtick down. He'll definitely have opportunities in this debate to turn Ryan's abstract haymakers about the deficit and budget into real policies with real consequences for ordinary Americans. Will Biden strike swiftly on this question a couple times, or will it be a reprise of his DNC performance, in which he informed the American people in about 327 different ways that Osama bin Laden was dead, Obama had done it, and that an American flag had been planted in his corpse?
What to Watch For: Ryan
1. Its the Bigtime: while Ryan has a national profile, this VP debate is certainly the biggest moment of his political life so far. Ryan has also mostly dealt with chumps in his electoral campaigns, and does not have Biden's record of seeking national office. Look for signs that Ryan is flustered or confused as indicators of the uniqueness of this stage. I expect him to do well if he confines his interventions to relatively abstract pushes on government spending and taxation, which would be an intelligent course of action.
2. Correct Biden, but Don't Be Mean: This is where expectations matter: Biden has a reputation as the Democratic Party's cranky old uncle or grandfather. On the one hand, this causes folks to not listen to him all that much. On the other, this means that taking unnecessary potshots at Biden could come off extra bad, especially given his personal history of tragedy. Ryan will want to hammer Biden when he gets into one of his riffs about "everyday Americans" but Ryan has to be very careful not to come off like a responsibility minded middle manager when correcting him. Americans don't like deficits, but they also don't like bureaucrats.
3. Women's rights: The "legitimate rape" flap has created an opening for some discussion of reproductive and gender rights. Biden can throw haymakers on this issue, while Ryan has in the past sponsored some quite right of center political approaches to the issue. Women really came out strong for the Obama campaign in 2008. If Ryan gets cornered into talking about gender issues it can only come at an opportunity cost with other news items (Libya, the economy, deficits) that are far more beneificial to the GOP.
What to Watch For: Both
Any references to Paul Ryan's ridiculous workout spread. Also, a giant eagle armed with a laser the annihilates budget deficits when it bursts through the auditorium ceiling.