I have a mid-2012 13" MBP (non-retina). I bought it in the first week of October, so it's still under warranty. Since then, this last week, I've noticed a large build up of dusk behind the screen. The dust is most visible when the screen is not on, but when it is on the larger specs of dust look like dead pixels. The dusk goes from the bottom of the screen (below the MacBook Pro lettering) upwards for about 1 1/2 - 2 inches. I'd estimate there are 50-75 grains of dust. Also, if I press on the MacBook Pro lettering it seems to not be touching the screen tight, if that makes any sense? Do I take it back under warranty and see what they say at the store? Has this happened to any of you? And do you know how long it'll take to repair?