I work at an Apple Authorized Specialist (basically a combination Apple Authorized Service Provider and Apple Authorized Reseller) and for the past month, we have had one of the new 21.5" iMacs on display. Just this past week, we were finally able to put one of the new 27" iMacs on display. Now with both machines on a clean desktop using the default Mountain Lion desktop wallpaper, the display of the new (Late 2012, mind you) 21.5" iMac is already showing signs of yellowing where the 27" one clearly hasn't. I've heard horror stories about display yellowing in iMacs from Mid 2007 all the way through the Mid 2011 models, but I hadn't yet heard anything about these iMacs, and I figured that with a dramatically redesigned interior there wouldn't be any yellowing issues. Has anyone else seen this with the new 21.5" iMac, or the new 27" iMac for that matter? As an Apple fanboy that is outspoken against the iMacs, I had thought that the 21.5" iMac of the current generation seemed to be more reliable and free of issue than any iMac in more than half a decade. Am I wrong here too?