Was more specific on national-security matters than on domestic subjects. Offered more detail on a range of topics, compared with Palin, but oddly, gained no particular edge from his greater familiarity with national and international issues.
Uncharacteristically tentative and nervous, and sometimes spoke too fast. At times he appeared drained of the passion that animated his strongest debates as a presidential candidate. Grew more intense near the end, but without much personality or fire. Still, reassuringly stolid and tough.
Relentlessly criticized the Bush-McCain-Palin economic policies. Came across more with sadness than anger in deriding his longtime colleague McCain, whom he repeatedly called "John." Did next to nothing to try to force Palin into errors, which was likely a calculated strategy.
Paid particular attention when responding to challenges to Obama's record on taxes. Often jumped in to correct or clarify a point (although his familiar use of the moderator's first name may have raised the hackles of some observers and the moderator herself). Was careful not to lose the upper hand when confronted with Palin's confident charisma.
Just as Palin kept her head well above water, so too did Biden keep himself under control, staying on message and away from long-winded, condescending and self-serving responses. Perhaps more stilted and tense than usual for most of the debate, but he never forgot who is at the top of the ticket and the immediate goals of the campaign. If he reviews the videotape of the debate, he will likely see some missed opportunities to give a slightly different answer in a slightly different way. A solid performance without fireworks, which may best serve the Democrats at this moment.