Hi, about the iMacs, i have not experienced any whining of any kind so far ( have it for over 2 months now ). I had windows on it and mainly used it to play games, that should max out the CPU, and i did not hear a thing, in fact its completely silent. i should prolly note that i played HalfLife2, HL2 Deathmatch and Counterstrike Source, with the last 2 having all settings at max ( apart from anti-aliasing ). On OS X i played Doom3, which pretty much made the CPU go all-out, again, silent. Never had heat issues, never had anything like the macbooks. i do hope they fix the heat/whining/discoloration soon because i'd realllly like a macbook myself.