I have a 3-month old Macbook. It seems that the layer of plastic that connects the underside of the chassis to the keyboard (the whole upper sheet of plastic) seems to seperate slightly (1-2mm) from the lower chassis. Also, the battery case seems to seperate about the same distance from the surrounding chassis. Is this normal/worth visiting an Apple store about? I'd be surprised if this was due to beating up my Macbook. While it has taken a few tumbles, they were from below waist height, and did not cause much lasting damage.