That's a good question...
It could sell very well since it's much less daunting than previous Zelda games (controls) and given the immense sucess of the DS.
Hopefully PH turns out to be a worthy installment to Zelda that will keep customers wanting more.
When I played Twilight Princess, I really felt as though, EAD pulled out their penis and pissed on all other developers out there technically and artistically, and then raped them. The games lighting, scale, and sheer size is like EAD saying "look what we can do on a Gamecube", especially those draw distances. And all on 1.5GB.
After looking at these screens I feel as though they will do it again. I also think they will put even more effort in, since they haven't exactly go the appraisal they were hoping for.
Lets see what EAD can do on a mobile phone processor. Hell I wouldn't be surprised if they managed to get heatwaves over those flames. And good draw distances in too. Their programmers must be some insane MF's. good on em'.
Would Nintendo change up the game just for Japan? Western Europe, and NA love us some ****ing Zelda damnit.
edit: By change, I mean any possible change in gameplay, art direction, storytelling etc. that will appeal broadly to a Japanese audience, ignoring the rest of the world who has supported the current revs (TWW, TP) with millions in sales.