It makes the most sense on the Wii, IMO. Cheaper to develop for (thus, the same budget can go further). KH is a cartoony series, thus doesn't really benefit as much from the PS360 graphics. The action oriented combat also lends itself to the Wii, IMO. . That, and in Japan, the main market SE would be targeting, the Wii outnumbers the PS3+360 around 2-1.
The cartoony atmosphere does lend itself to the Wii audience. OTOH, Wii gamers, as a group, have appeared reluctant to purchase more involved titles.
That being said, I'm sure Sony would like to keep it on the PS3, and whichever system it comes out on, I'll be sure to pick it up.










