We all know that about mid-April, there some reports of production shortages of the iPad LCD screens, and Apple was scrambling to find enough to meet the end of April ETA. Well usually Apple has the manufacterer inspect things like the LCD for "quality". What if this time they were more lenient because they were kind if desperate? The yellow tint issue is more subjective than anything, and if the user hates it, apple would replace it, once the second manufactering batch rolls in (the first batch is pretty much sold out everywhere now).
I mean, this has happened before with the Nvidia MacBook chips (wasn't it the 8600?)