This compares to the UK style of interview, where the challenge is to avoid the question, rather than simply to give a false answer.
In terms of weaknesses, I think Biden's arguments are excellent for the intelligent listener, although I suspect some of the subtlety and much of the detail is lost on the average listener. He needs to speak more in headlines.
Palin is alternating between "nucular" and "nuclear", but completely fouled up "Kim Jong-Il". She is very heavy on rhetoric and ad hominem, especially through the foreign policy section, but that was expected.
I also note that the "who voted for or against what" is FAR more complex in the USA than anywhere else due to the way composite bills are constructed and passed. One might legitimately vote against a bill on the basis of some obscure measure, while agreeing with the body of the bill, and the ability to filibuster means that utterly irrelevant measures may get included in an otherwise straightforward bill.