Two years after teen heartthrobs B2K threw in the towel, Omarion, their vocal center of gravity has resurfaced with his solo debut, the aptly titled O. Despite such high wattage producers as the Neptunes and Rodney Jerkins, the toothsome singer sounds much the same as he did when he fronted the boy band, except some of the tracks are a little racier than the stuff his former outfit put out.