On my second one, bought originally 1.5 mos ago, got replacement 1 mo. ago. One dead pixel, very soft whine (not audible to my ears below brightness 14), light yellowing near the bottom, I see the gray band sometimes on full-white screens.
It's far from perfect, I wish Apple's QC was better, and I could have certainly had better timing, but what the hell, I actually love the thing anyway. I think their current level of quality is certainly challenging to the perfectionist, but the overall product remains sublime.