Don't know if this has already been posted but I'll bring the info to those know who don't know. I was speaking to a college at work (we sell laptops, tv's etc) and he said he had had to deal with a customer returning a MBP because of yellow tint. I was interested since I have the same problem with mine. Apparently, the problem is that there is a yellow sticker at the side of the screen that is there to act as a seal - so if it gets broken Apple know you have tampered with the screen. But, this yellow sticker reflects light sometimes and is projected onto the screen, hence causing this problem. I'm not sure where the sticker is, but it might be near the last 3rd of the screen ; possibly why people notice the bottom of the screen being yellow. He said that he called Apple, and they confirmed the yellow sticker problem, and said it would be a 2 minute job opening the screen and removing the sticker. I'm going to take mine to my local Apple vender and see if this is truely the case - nothing fully confirmed yet.