I totally agree with Michelle about the risks facing Biden in that VP debate. The contrast between Biden and Palin will serve the Democrats well in almost every respect. But, if you asked me to name the high-profile Democrat most likely to make a condescending remark in this situation (albeit inadvertent), Biden would top my list. (Please, please, please banish the phrases "young woman" or "young lady" from your vocabulary, Joe. Please.) I think about 90 percent of Biden's debate prep should focus on how to interact with Palin respectfully, ten percent on everything else.
P.S. My wife had a good solution to the debate problem this morning: Biden should spend most of his time focusing on McCain and engage Palin as little as possible. Though you don't want to completely ignore her--that could also be perceived as a slight.