Ever since I upgrade to iOS4, I have had problems with my screen. Though it wasn't immediate, the next morning after upgrading my screen went dim in the middle of using the device. I put it to sleep, turned it back on, and it was bright again. It stayed that way about 45 seconds, went dim again. I don't think it has anything to do with iOS4, just coincidence. I came home, plugged it in to the Mac, and it was bright. After charging a while, I took it off the charger, started using it, and it was bright about a minute, then went dim. When I say the screen goes dim, it is dimmer than that stage when the screen goes to power save mode after like 2 minutes. I have to strain to see anything, or to even tell that it is on. There is "something" there, and I can recognize it as my home screen or whatever. Anyway... does anyone have any ideas about this? Anyone experienced something similar? I bought it in October, at Fred Meyer, but if I need to, can I return it to an Apple Store? I don't think I have the original documents (I just moved to a different town) and definitely don't have the receipt, but I'm within my year warranty.