Screen-shotApple made a new update available today for the 27″ iMacs. Hopefully this will solve the whole screen flickering issue. It’s a firmware update to the ATI HD graphic cards.

Updates the graphics firmware on ATI Radeon HD 4670 and 4850 graphics cards to address issues that may cause image corruption or display flickering.

I have already returned my flickering iMac so I can’t test out this fix.