Winter 2008 - Spring/Summer 2009.
If they release it for the 360 they mind as well release it for the Wii, also. But I'm not too worried since the 360 has crap graphics compared to the PS3, but it might mean it may lower the graphics on the PS3.
FFvXIII is still PS3 exclusive, but I don't think it will be for long becuse of this crap news. But at least PS3 is getting a Microsoft exclusive (Bioshock).