Apple just exchanged my iMac that had overheated and kept freezing up etc. with a new replacement. We picked it up yesterday after they transferred everything from one iMac to the other. It worked flawlessly all yesterday afternoon. So I though excellent! Everything is good with this one. It didn't get hot, it did freeze up or anything and all was well...until today... My son just turned it on and nothing...the screen flashed and then just sort of glows, no chime nothing, it just sits there. You could hear the fans start and the drives start but then the screen just sort of glows blue...We shut it down and tried again...same result. Maybe there is a problem with the iMacs...I am now 2 for 2 in less than 1 week. I'm not so sure I am liking this iMac now. I called the Apple Store and they said they will exchange it yet again...now I'm not so sure I want another iMac. This stinks! I have some software licenses that I have to pull off of it so I had to make an appointment at 7:30 tonight with the Genius Bar to see if they can retrieve the license.