It seems that there is official word from id Software concerning the number of discs and install size of the game both the Xbox 360 and PS3, where the latter will have an easier time with the game as it arrives on a single Blu-ray disc, taking up 8GB of hard drive space during the installation process. Seems huge for a console (computer owners have long gotten past the shock factor), but the benefit you receive in return would be shorter load times during play.
As for Xbox 360 owners, you will have three DVDs to take care of, and even more pain can be expected when you install the game since it takes up to 22GB of space on your Xbox 360. id Software has addressed this issue by letting you install sections at a time if you so desire. Nice to know no disc-swapping is involved since the game was designed in different modules to fit on different discs.
Are you ready for some Rage?