You're second point about the team moving around makes sense, but even so, SE is still probably going to want to keep most of the PS3 experienced workers on a new PS3 project to make it go faster and be higher quality. Having people learn new things=slower=more money spent on development (wages, etc... normal costs) and the end result out later than it could have been.
Thus, if the main KH team already knows how to use the devkit for PS3 after they've had it all done on the computer or during the process, it will still go faster than if they had to learn the Wii-U devkit, because, since it's a newer system, I assume most of them haven't had much experience with it.
What matters is that they will have the devkit understood and will have experience with it once Versus is done and thus it would be efficient for them to use that knowledge on another project. That's all I'm saying.
Like you said, in KH, graphics aren't the highest focus. But if Nomura was to weigh his options if it came to graphics it wouldn't matter since they are at the same level.
I don't think it's impossible for KH3 to be on the Wii-U, I just think it's unlikely. That's it.
Anyways, my original argument was that I personally thought it was most likely for KH3 to be on the PS3 and I gave my reasons why. I really don't want this to turn into a giant argument thread and pointing out how inexperienced I am with game development. We should just probably agree to disagree and leave it at that. I don't want this to ruin the thread for the rest of the members here who want to discuss KH3 on the wii-U and the article itself.