Dragon Quest X is an online role-playing game. Know what online role-playing games have? Subscription fees, and DQX appears to be no different.
On the game's official site, it lists standard info like platform, release date, and price. Here's a look:
Platform: Wii/Wii U
Release Date: (Wii) Planned for 2012/(Wii U) TBA
MSRP・User Fee: (Wii/Wii U) TBA
The fact that there is a "user fee" next to the MSRP indicates that players will pay to play DQX. In that regards, expect DQX to be an online game in the truest sense.
More disconcerting, however, is that the Wii version is slated for 2012, while the Wii U version is TBA. Certainly, Square Enix could release them both in 2012, but with the company's track record of getting games out quick, we could be looking at a 2013 or beyond release for the Wii U version of DQX.