I'd prefer it to stay with Sony, but I can see the marketing opportunity of moving to the 360. I'd feel slighted as a fan of the series, but it would be a good business move. Insofar as the story is concerned, have we actually SEEN inside Kingdom Hearts? Sure, we've stopped people and things getting into it, taking it over, siphoning off the power and whatnot, but we've never been shown inside it. I don't think that the sequence against Xemnas in KHII counts, really...
Also, we were shown the Cornerstone of Light... stands to reason there must be one of Darkness or the like, right? Everything has to be balanced. I'd like to see them do something with that. As for worlds, there are any number of Disney films they could pull out - Snow White (as was mentioned), the Pixar catalogue, Atlantis, a proper 101 Dalmatians world... so many to choose from.
There is quite a bit left in the franchise so I really wouldn't mind a third. In fact, I'd be quite happy to play it if it's anything like the predecessors.
