I have a 2.4 17" MBP hi-res (matte if that matters) that I got last october. I've noticed that every now and again if I leave the screen up, let the screensaver come on and then let the screen go to sleep upon waking (by touching the track pad or by hitting the spacebar) there is sometimes a bluish/grayish tint to the screen. If I close the lid and leave it for a minute, then open the lid again it goes away, or if I restart it goes away. Anyway, again it doesn't happen all the time, but it's annoying when it does. Anyone have an idea what this is?