There's some grumbling going on in forums and other blogs about Core i7 iMacs showing up DOA much more often than you'd expect from a brand-new computer.
The two types of issues we're seeing most are cracks in the screen and a completely dead computer on delivery. What's most plausible is that the packaging just wasn't designed to handle the size and weight of the giant 27-inch iMac as it gets tossed around the cab of a FedEx truck. Apple has so far been extremely responsive and effective in making repairs and exchanges, but it's still a discomfiting sign—if you're about to buy a new iMac, you might want to wait and see if Apple announces a fix for whatever's going on before you take the plunge. [Apple Forums via Engadget]