This is interesting. I had a yellow blotch on my iPhone 4 (no pictures since it showed up on the front page just as I was about to take them). I spent a lot of time messing around with it, and I look now, and the blotch is basically gone. (You can still barely see it, though it's not as bad as before.) I don't know if that is technically possible, but for me, my iPhone seems fine. We'll see how it is in the morning. Anyone else?