Square Enix revealed this for the Wii years ago but never came to light. Now their revealing it again but this time with an online focus. It will be out for the Wii and Wii U next year and will be called Dragon Quest X Online. Yes, the latest installment which makes the Dragon Quest series reach double digits will be in a form of an MMO. It is still not certain what type of MMO it will be. Will it be the traditional MMORPGs? or just a small group similar to Monster Hunter Online(only released in Japan). Regardless of how this game will be, Andriasang mentions that the Dragon Quest X Online website contains a TBA on "usage fee". Still not officially confirmed but knowing how this goes, it will have the traditional monthly fees aside from the initial purchase of the game.
Dragon Quest X Online will have Wii and Wii U compatibility so players can play with each other no matter what version they decide to pick up. Of course, Wii U will have an advantage since it will have improved graphics. 3DS compatibility was also mentioned but not confirmed at the moment.
In regards to gameplay, the only info out is that players may craft weapons and own their own property. They will also include a feature that makes players use their friend's character as an NPC when their offline. That's it so far.
Level-5 developed the last 2 games but so far only Square Enix was mentioned in this project.
The game is set for a 2012 release and since its also developed for the Wii U, a release date of Dragon Quest X Online should be around the time of the Wii U release. That's a long way from now. So fans of the series don't hold you breath waiting for this one. They also mentioned a beta before release.
Trailer is now up on YouTube together with a lengthy presentation of the game. You can't understand a single thing, but you get to see the game in action.