Second laptop in a row went back. The first one had a defective GPU diode or something (the screen went bonkers when I charged the machine), and the problem occurred too early for me to notice any yellow tint.
The second one looked superb and behaved normally until the first ostensibly white window: The tint was glaring!
I returned that one too and, until today, I was expecting a third machine. But I finally reckoned that a computer purchase doesn't deserve to be a stress-inducing experience, so I called Apple and got a refund.
I am tempted to opt for a Blackbook and upgrade memory and hard disk, but I will wait until Apple gets serious about quality control. Apple customer service is truly exceptional, but sadly it is also the best that the company can now offer.