They most likely will release it for the computer. And if they follow their past releases, it wont be for awhile. They usually refine the game to make it better than just a normal console port. They usually do a good job porting the THPS games to the computer, I have 2 and 3 and they are both pretty decent, with better textures, higher resolutions, and smoother gameplay than the console version.
You probably will need a halfway decent computer to run the game... I'm assuming probably a 700mhz processor or above, with a 16MB 3d card or better, and like 128 MB of RAM or better.
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