The DS-exclusive RPG might actually be a cross-platform release, according to new rumors.
The idea of a cross-platform Dragon Quest IX isn't entirely far fetched. With Square-Enix emphasizing wireless multiplayer for DQIX, having people play on the go with people who are playing at home seems like a natural fit. Furthermore, the existence of a console version might please some who prefer to do their dragon questing in the comfort of their homes.
Finally, there's the example of Final Fantasy Crystal Chronicles: Echoes of Time, a Square-Enix release for the Wii and DS. Echoes of Time on DS and Wii are the exact same game (they even look alike), and multiplayer works wirelessly, across both plaforms simultaneously. Could Echoes of Time be a practice run for Square-Enix's bigger cross-platform show?
Dragon Quest IX is dated for a March 2009 release in Japan.