Square Enix announced in the newest edition of the Japanese magazine Famitsu that the game will be heading to all three major console download services as well - WiiWare, Xbox Live Arcade and PlayStation Network. The magazine explicitly refers to the XBLA and PSN versions as "enhanced ports", while it doesn't call the Wii version a port at all - Could it be a totally new game?
The WiiWare version is called "Crystal Defenders R1", features Wi-Fi support (Which probably means DLC, because it's a single player game!) and will cost 1000 Wii Points. It's coming out rather fast, too - Japan will be getting the game next Tuesday! The game has not been confirmed for release elsewhere yet, but seeing as this is Square we're talking about, it's quite likely it will be released everywhere.
Famitsu also has some screens of the WiiWare version - We've added these as screenshots until we get better ones.
Update: Behold the Japanese trailer: