For fans of straight rock 'n roll, "jazz" might be a bit intimidating. But not the way the Pianos play it. The Oberlin, Ohio, up-and-comers take a distinctly pop turn with the form, pitting jubilant sax and trombone against playful accordion and syncopated drums, their wandering trills all grounded by solid, strumming bass. Tonight they're joined by jam-brothers-in-arms Gutbucket, who are fresh from a BBC-sponsored performance at the London Jazz fest. So forget the blasé snaps — this night's about dancing.