The spousal unit summed it up well - it's like Marge Gunderson arguing with Jack Nicholson.
No surprises thus far. Biden's familiarity with public speaking and debating becomes more clear as the event goes on, but Palin isn't doing badly. The usual suspects will say the expected things when it comes time to make claims about who won.
Good for Biden taking on the "maverick" bullshit. Almost as good as skewering Obama in the primaries for not being ready to lead. And nice steal of Hillary's when you're knocked down, get back up imagery.
No disasters, no upsets, and marginally more interesting than the first debate.