The Lil Jon-produced “Touch” is little more than a tabla riff, an 808 kick, and a handclap-Amerie‘s singing is almost superfluous; it‘s a club beat that anybody could be on. That‘s why you‘ll hear it incessantly for the next six months. Instead, stick to the duet with Nas, “Man Up2,” which is up there with the best Faith or Mary J collabos-a funky, methodical MPC hip-hop loop and killer Am hook. Tight.