This is very weird, I just bought an iMac to try out and I installed LR3 on it. I copied my catalog and images, to see how the mac works.
First off the iMac display looks so much better than my $600 HP LP2475w that it blows my mind.
But what is really weird is even after calibrating my HP (for the 1000 time, it never seems to calibrate well). The HP looks very yellow for a particular image I loaded to compare and the iMac is dead on. The strange part is both have a white balance setting of "As Shot" but the Windows box using the HP monitor has Temp 5850 +36 Tint, the iMac has Temp of 5750 +27 Tint.
Both are showing "as shot" yet they have a totally different white balance setting.
If I set the Windows box to match the iMac white balance settings it changes from "As Shot" to "Custom" and if I change it back to "As Shot" it shows the old Temp and does not revert to what the iMac is showing.

