Kamiya didn't actually say that precisely. He was asked how he would feel about it, and he said it would be great. He did not say "I want to do it". He may have just been being nice. Or he may mean that he'd love it. But the OP title is a bit misleading. Still, I think it would be in both companies interest to do so, for sure.
@fauzman
Mistwalker did act somewhat as a second party to for awhile. But they worked with Nintendo most recently, and what little indications there are of whatever they're working on now, point to it again being a Nintendo system project.
But as for Platinum, I think between their Clover days and now, they've made a lot of great stuff. I don't like EVERYTHING they've ever done, for example I really wasn't into God Hand, or MadWorld, or Bayonetta at all. But Viewtiful Joe was a neat throwback beat em up, Okami was amazing, and Wonderful 101 looks cool, and was fun from what little the demo showed me.
