I'm just playing the opening sequence right now, but if you have any questions about the game in general that I can answer without spoiling any story elements, please ask here and I will check back periodically and answer what I can. Please keep in mind that I did just start the game, so some questions I may not be able to answer yet.
I have the 360 version. Popping in Disc 1 prompts a mandatory in-game install process. When this is completed (after about 10 minutes), you are asked to put in Disc 2 and then the game starts.
Q: How did you get the game early!??!?
A: I know people