While I won't be buying the game (fighting games just aren't my cup of tea) if I did, it'd be motion controls all the way.
It's the way it was designed to be played, the previews pretty much all say they work great, and it looks like the kind of game where it would be very satisfying to whack an enemy by physically throwing a "punch".
I must say, as someone who loved the Wii and enjoys well implemented motion, it pleases me to see them making something of a comeback.








