At last night’s pre-E3 Microsoft press event about the XBox 360, it emerged that only the “best selling” XBox titles will be compatible with the XBox 360. Eurogamer has the details here. This sounds to me like the hard disk will include pre-compiled binaries of the most popular games. The program code for games such as Halo will be recompiled and made work for the changed hardware (both CPU and graphics chip have been changed for the XBox 360), and when the XBox 360 sees that you have inserted the disc from one of its “compatible” games, it will run the compatible version of the code from the hard disk, and read the game’s data files from the DVD as usual.
This approach is quite a good one. It means that you will still be able to play Halo and Halo 2 on your XBox 360, along with all the big name games from the XBox, ensuring that the XBox 360 has some existing games to compliment the relatively small list of launch titles so far announced. It is also possible that more games will become compatible over time via downloads over XBox Live. Publishers may be able to provide a XBox 360 “upgrade” for their existing games which can be downloaded as desired.
However, the PS3 details have been announced, and it’s looking very good. The XBox 360 will have a big challenge on its hands, and I don’t know if the Master Chief will be enough to win the contest this time round.