From First Read (emphasis mine):
As For Biden: He had a senator’s grasp of the facts, and we mean that mostly as a compliment. But longtime Biden watchers could tell he was struggling with how to deal with her. He spent the first half of the debate on the defensive. It wasn’t until the last half hour that Biden found his inner-Goldilocks and found the “just right” tone in dealing with Palin. In fact, Biden ratcheting up his seriousness and emotion may have made Palin’s folksiness seem tonally off for a little bit toward the end. If Palin started strong, Biden proved to be the better closer. As we said yesterday, if Biden turned out to be the subject of post-debate chatter, then he had a bad night. As it turns out, he’s not the story and the Obama campaign is satisfied with that even if the media elite is scoring this better for Palin than the insta-polls.