A lot of people simply lack experience with this sort of thing. My calibrated screen has ideal whites right now. If I bump up the color temperature, then whites will initially look blue. After a period of time my perception will adjust and that will become the new normal. At that time, when I transition back to the calibrated values again, whites will appear yellowish.
I have a relatively cheap piece of copier paper here. It looks white. However, I can go to the store and buy Super Bright paper. It's chemically treated and will make what I have now look yellowish. However, it's the treated stuff that's not right.
There is a reason that people doing professional video calibration use instruments and it's that they realize their eyes cannot be trusted. They are biased by comparison, ambient lighting, etc.
Hopefully Apple will add a feature that allows people to adjust their iPad color temp. This would certainly help all those people that don't have an outright defective device.
