I went to Best Buy yesterday and they just got the new imacs in and had on display side by side. The 21.5 display was not as bright and vibrant as the 27 display. The apple and best buy guys could not tell me why the difference. The settings were checked and found to be the same for both machines. I was going to get the 21.5 but now not so sure. I definitely like the brighter 27 better. Is this normal? Why is the 27 brighter? Has anyone else noticed the difference? Thanks in advance.