I just wanted to share my experience in the yellow tint issue of 21.5" iMac (Mid 2010 model), because I really appreciate this forums. First, I have been using Mac for 15 years. I love Apple. I love Mac. That's way I expect the best from Apple and am picky about the quality of Apple's products. I ordered iMac 21.5" base model on Apple online store and received it on 19th August. Immediately after I started to use it, I noticed the yellow tint on my iMac. But it was not a big problem for daily use and at that time I thought it may be due to the color profile. Then, just 14 days after I received it, I found the yellow tint issue of iMac in this forums. I called the Apple support and he asked me to go to the genius bar in an Apple retail store. Last week, I took my iMac to the genius bar and explained everything to him. Surprisingly he immediately offered me the new replacement. Although I did not take my iMac's keyboard and mouse with me, he exchanged my iMac for an unopened brand new iMac. That meant I got another brand new wireless keyboard and mouse. I was very happy with this Apple's service. However, the replacement iMac has the yellow tint, too. I was trying to live with it, but I could not. I called the Apple support and yesterday went to the genius bar again. This time I talked with a store manager. He said the yellow tint was within a range of the LCD variation. I checked 5 of 21.5" iMac in the store and they all had the yellow tint. When I compared 21.5" model with 27" model side by side, the difference was very clear. The LCD monitor of 27" model is perfect. The monitor of 21.5" is inferior. The manager agreed with that all iMac 21.5" has the yellow tint. At that point, I finally gave up looking for a perfect 21.5" LCD and decided to live with this iMac 21.5". So, my conclusion is that yellow tint is the common issue of 21.5" iMac. Please do not waste your time looking for a perfect 21.5" LCD. If you want a iMac with a perfect LCD, you should buy iMac 27" model. Thank you!