Striking: Obama's been directly engaging, even preemptively bringing up, McCain's experience critique. "Senator McCain thinks I don't understand," he said earlier. And just now: "Senator McCain thinks I'm naive and green behind the ears, while he's somber and responsible ..." I think it works -- Obama claims words like "naive" and defuses them a little, mocking them gently, before McCain can drop them first.

--Eve Fairbank