Hi, I'm being pretty satisfied with my new iMac overall, especially with the fact that the screen doesn't have a yellow tint to it, and that the hard drive is whisper silent. (and doesn't hum or resonate on my desk) But i can't stop wondering if it's normal and acceptable with the extreme whiting from the backlight on black backgrounds i'm seeing on my unit. When i wake it up from sleep and get the logon screen, the black background in a dark room (on medium contrast) is pretty far from a perfect black, like for example, on a quality plasma TV. Another thing i'm noticing is that, if you move a small white safari window around on a black desktop background, there are some areas of the screen that have a very very slightly darker color, like a shadow, but only visible if i look for it. I think it's an irregularity from the led backlight since the screen is clean of dust. Do you have this slight deviation in white too? And what's acceptable on a LCD like this, is it too much to ask for an iMac with none of these minor imperfections. I did buy it for the awesome screen to begin with, and i somehow feel that with all these screen issues, i might have one that is as good as they come, and wont get a perfect unit no matter how many times i send it back. Oppinions? BTW where i live, it's around 3400$ for this BTO i7, 1TB, 4GB RAM, 2GB VRAM....so it's not like it's a cheap machine.