Khuutra -- Agree with many of your points.
I would add though I think "the shoe has already dropped" as it were.
Square-Enix is not going to second guess the Wii any more. They already made that decision by putting Dragon Quest X on the platform.
They could have put it on the DS for instance, but obviously they feel the Wii can be as successful of a platform for them.
That means a lot more is coming, not just DQX. No way does Square-Enix leave their lead Japanese RPG to fend for itself. If they still had questions about the Wii it would be getting DQ Swords 2 rather than DQX.