500k or more would be monumental success in Japan. The thing with Japan is that the is perceived as an even more of casual or family machine there over in the West.
Part of the reason Nintendo probably is pumping and publishing this game is because they know you have to have some meat on its system for the userbase to buy these type of games and to attract publishers to try to publish them on their syste. The only games that sell decently that aren't from Nintendo are liscene games, and even Nintendo has had a horrendous time pushing their non casual or Mario games in Japan on the Wii.
This is less about saving JRPGs, it is about saving any cred the Wii has of being more then just a casual machine and to try to extend it into the next console.
