Today I was at Fry's to look for a couple of things and thought I'd see if they got the new iMacs in yet, they hadn't had them the last time I was looking. Now they did and I checked the screen out very carefully and it was much, much better. I'm still angry that Apple made the very stupid decision to put a 6 bit TN panel in instead of the 8 bit ips panels that Apple monitors have always been, but at least the color and tone was even over the whole screen this time.
So it must have been a bad batch in the first ones that went out and they seemed to have fixed them now. The screen looks good but it's still glossy, another really bad choice by Apple. And as good as this screen is it can't hold a candle to the screens in the last generation white iMacs that I ended up buying. Even the 24", which is an 8 bit ips panel, doesn't look as sharp and clear as my 20" because of that god-awful gloss on it.
But at least they have a usable screen now in the 20" imacs. A non-pro might not notice the lower quality of the new screens and if the glossy doesn't bother you, now you can at least be sure you aren't getting a monitor faded out on the bottom and too dark at the top. Although I bet there are still a few of those floating around.