I agree mostly and you only have to look at their track record recently:
Halo 2 on PC, Halo 3 not.
Fable on PC, Fable 2 not.
Gears of War on PC, Gears of War 2 not.
Truth is, Microsoft wants true exclusives like Sony have on the PS3. Reasons to shift a console, not reasons to play it elsewhere.
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