Interestingly, my scenario is different. My black iPad 2 has decent whites, with just a tinge of yellow cast. My New iPad 3 has whites with a definite bluish tint, and absolutely zero yellow cast. My new iPad looks like your iPad 2 (the one on the right?).
Compared to my iPad 2, the new iPad is almost too "cool" in color. I like the whites better on the iPad 2, I think.
If I'm not comparing side-by-side, the iPad 3 looks fine, though.