I actually agree with Stu on this. In terms of the game being appreciated, and units sold, the PS2 would be the only viable choice.
If there is a reason that this game MIGHT be on Xbox, then it would either be because the game isn't capable on PS2 (which I don't think is the case, because developers are actually starting to realise the true power of the PS2, though not as much as the Xbox's (or GC), which is a total guess mind you), in other words, greater things can be achieved quicker, or one of the other obvious ones, MS paying for rights on this installment.
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