The Senior Vice President of Square Enix, Shinji Hashimoto, has started the super secret Square Enix press conference today by clarifying Final Fantasy XIV's exclusivity details. The game is currently pegged for the PS3 and PC, though "in terms of other hardware devices, including Microsoft's, we're considering all possibilities."
It's not confirmation that we'll see the game on the 360, but it does mean that Final Fantasy XIV could end up being a timed exclusive on the PS3. It was also confirmed that the game would launch simultaneously worldwide for PS3 and PC in 2010. They are planning to be truly cross-region and cross-platform -- a rare thing for an MMO -- but this may change depending on how the beta test works out.