The thing I liked best about Jimmy Fallon's first week in the spot vacated by Conan O'Brien were his hands, made all the more conspicuous by the fact that they're emerging from the suit sleeves that are part of the official late-night uniform. He gesticulates with a tentative, likable vagueness, like a salesman too modest to describe the product he's pitching. Fallon is a bit damp—he doesn't have O'Brien's talent for blazing into craziness. But a gag about flashbacks sputtered into something distinctively ridiculous, and a parody of The Hills was perfectly, knowingly inane. With guests he's politely excitable, laughing and rushing through his words. Overall, his potential is first-rate.