I made it to the Apple store to see about an exchange. I will say that the lighting in the store sucked, and it was difficult trying to see screen tinting in the store. The Genius I spoke to originally couldn't see the yellow corner on my iPad, but when I pulled up a white image, he said that yeah he could see it. Again, I was somewhat torn about taking my iPad in because in other respects it was perfect--no dead pixels, no backlight bleed whatsoever that I noticed while watching trailers and such. There was dust stuck under the bezel near the top (not on the screen) that I didn't care about.
The store let me inspect one new iPad but said they would only let me do the one exchange. I found it really difficult to examine it in store. It was definitely not perfect but I wasn't needing perfect. The top right corner was darker than the others, but it was preferable to my original iPad because the original one I got was dark and yellow, so it would actually shift colors of white/grey screens in that corner only (visible especially for the split keyboard, etc). I also prefer the "bad" corner being in the top right because I spend less time looking at it with normal landscape orientation. The top left corner (in portrait mode) is often where keyboard is, etc. (in landscape orientation), whereas the top of most apps is covered by a bar, etc. (I know you can change which way you hold the iPad, but with some covers and stands it's easier to keep it a certain way).
I accepted it and brought it back to work. Looking at it I am still pretty happy with it, with one problem. I have bad backlight bleed on the top left hand corner that is visible in normal use watching movie trailers off of youtube at ~60% brightness.
This isn't something I could check at the Apple store, since it had rather bright lighting. I don't intend to watch movies much, mostly I wanted the iPad to write on and read work documents off of, so in practice backlight bleeding will bother me much less than a yellow corner. I'm going to take it home and try watching a full length movie or TV show to see how much it bothers me.
I don't know if there are "perfect" screens out there, I just think it depends on what each customer wants to use the iPad for and what they're willing to live with. I like that the keyboard on the iPad no longer shifts from yellowish to blue like my old one did. but it wasn't really worth making the trip to the store for me, I could have just done an online exchange because like I said inspecting the ipad in store was pretty difficult (especially with an Apple employee staring at you the whole time. She was nice and polite and of course I see the need for it, but it was still not that great of a visit with all employees insisting they had never heard of this problem before and that they couldn't see any issues with any of the screens) and physically getting to the store was more challenging for me than it might be for others with nearby stores and cars. Anyways, sorry for writing a novel on the issue, just wanted to give an update of my experience.
Both my first iPad3 and the replacement are DM models, if anyone cares. I didn't bother asking for a DY because I'm not sure I buy that DY is better. First was a week 17 DM and replacement is a week 16 DM.
