There are some big laughs in "Austin Powers: The Spy Who Shagged Me," but they're separated by uncertain passages of noodling. You can sense it when comedians know they have dead aim and are zeroing in for the kill. You can also sense it when they don't trust their material. The first "Austin Powers" movie burst with confidence: Mike Myers knew he was onto something. This time, too many scenes end on a flat note, like those "Saturday Night Live" sketches that run out of steam before they end. "SNL" cuts to music or commercials; "Austin Powers" cuts to song-and-dance interludes.