This is happing all over the place, at least to the 500GB hard drives. Same thing here, I can't see the drive in the utility tray, i put it in my other older (2008) macbook 15 it worked and I formated it in 1 minute. when I put it back in the macbook 13 (2009) it didn't work. Frustrating to say the least, way to screw things Apple ;)