Square says that they will produce the game for the other systems, but that doesnt fit in with other plans Nintendo and Microsoft made.

Microsoft wants one bill for everything online having to do with the system. Since FFXI will be powered by PlayOnline, that is impossible, and neither company is thinking of changing their plans.

Nintendo, on the other hand, does not have an online plan and is going for a gaming only system, and does not want to integrate online with the system until it is proved absolutely necessary.

Therefore, unless companies change the plans they already made, it wont work for any system other than the PS2

-Rory