Wow. So much doubt for the little white box.
Porting DQX up to the PS3 makes no sense. It'd be like porting DQIX up to the PSP.
The Wii is not selling software unlike the DS. People cite the poor tales sales, but the DS hasn't done any better in comparison to the PSP. They cite the MH3 sales, when it's a console (with a paid subscription) vs where it became popular, on the PSP, a handheld. We see games like KH perform better on the PSP, should we conclude the PSP would have been a better bet for DQ?
Look at the big picture. Niche RPG's are meaningless in the face of Dragon Quest. Really, just ask yourself - why do you think DQIX sold so well? It's not as if the RPG's without DQ, Pokemon or FF on the box were selling millions. By the time DQX comes out, the Wii userbase should be over 14, maybe 15 million. Many other games will precede it, like more Nintendo games (including the RPG's), DQ remakes, or anything else that comes out in the next 2 years. The userbase will be ready by then. For DQ, they always are.
The game will clear 3 million, easily.