John Carmack perfers Xbox360 but support PS3 as well...

[Steel X]

ID software is working on a new title for the Xbox360, PS3, and PC version in the near future.

Maybe...it's Doom 4? :P lol

John Carmack Prefers 360, Still Supporting PS3 news from 1UP.com

 

[Foxrac]

Well, Cell processor is new tech in gaming world, also not for PC since PC games are use install under cell processor and hard drive. I means for console that PS3 is first to introduced new system and make game developers to get change and still learn to get usually with cell processor, it take some time to get experience and does well on PS3.