In Japan? There can't be too many. This is a country that despises the 360 with a burning passion, yet 360 units were flying off the shelves when they came packaged with the game. How many people do you think were banking on a port of a port?
Now that Japan sold quite well on the PS3 version, how well do you think they will react to the Wii, which has terrible third party sales? I just can't see it being profitable. Even if they do it, can't see it ending up over here, especially with Graces there to begin with.
They might go Symphonia and do a sequel, but it seems too soon. They've been working on Graces for how long now?