According to a Nintendo of Japan customer service representative, the 3DS will be region-locked. This means that if you import a Japanese system and attempt to play a North American game, it simply will not work.
As disappointing as the news is, I don’t think this should be a big surprise to anyone. After the DSi implemented region locking, there really was no going back. Nintendo has yet to officially comment on the issue, but I’d say this rumor is very likely.
Ninjas Face Off in an Epic LEGO® Adventure Spinning Onto the Nintendo DS This Spring
Burbank, Calif. – Jan. 11, 2011 – Warner Bros. Interactive Entertainment and TT Games are unleashing an epic family friendly adventure with LEGO® Battles: Ninjago for Nintendo DS™, the follow-up title to the highly-successful LEGO® Battles videogame. Scheduled for release in Spring 2011, the game complements the line-up of LEGO Ninjago products to be released starting today and going throughout 2011.
Produced by critically acclaimed TT Games and developed by Hellbent Games, LEGO Battles: Ninjago allows players to become a master of Spinjitzu, an art form in which characters spin and become tornadoes to defeat their enemies, as they restore harmony to the world. Players can choose to play both “good” and “evil” single-player campaigns, test their skills in a variety of Battle Mode challenges, or play with family and friends in exciting multiplayer showdowns.