I've had my whitebook since June of 2007 and gradually I have noticed on the top lid of the case there are very tiny black dots that are appearing and spreading across the surface. They are very subtle but they are there. I've never seen anything like it. I clean my macbook very carefully with Monster ScreenClean and never leave it out of the case or in the sun so i'm confused on how this could happen. Anyone else experienced this with the white polycarbonate cases?