Too early to predict where KH3 will end up. SE is quite busy with the other projects at this moment, including two KH spinoffs on PSP and DS.
KH3 can't afford to miss the NA market because KH series are even more popular here. If PS3 sales improve significantly (in US and Japan) after the release of some big titles in 2008, it is quite likely that SE will put KH3 on PS3/Xbox360 and have another KH spinoff for Wii. It should be fairly easy for SE to build KH3 on PS3/Xbox360 after they get enough experience with Unreal Engine when making The Last Remnant (am I the only one interested in this title?).
I do think Disney may play a role in the decision making for KH3. Will Disney give a hand to PS3/BD player? Interesting~
On topic: I prefer KH3 on PS3 than Wii.
It (PS3's market share) might hit 30%, but definently not more. ~ Neo
Flaming (Calling another user (any user) a fanboy is flaming.) ~ Machina-AX