According to id Software creative director Tim Willits (and confirmed by Joystiq,) Rage will require 3 discs on the Xbox 360 and an 8GB install on the PlayStation 3. In fact, many people rumored that this was going to happen, but most were predicting a two disc 360 version instead of three.
Fortunately, PS3 owners will be able to play the game on just one Blu-ray disc. For the 360 version of the game on the other hand, Willits highly recommends the 22GB install: “you don’t need to install all three discs. If you don’t have the space available on your hard drive, don’t stress. Install the first disc, the first chapter, the first half of the game, then when you’re done, uninstall and install disc two.”
Multiple discs seem like a thing of the past, especially as swapping discs in the middle of a game is woefully inadequate, but this shows that even the current generation of consoles still has some minor inconsistencies. In any way, it looks like this trend is going to continue, at least until Microsoft decides to inevitably accept the fact that Blu-ray discs are becoming the standard storage medium.