Games exclusively for the DSi will be region-locked. Cammie explains why...

While the upcoming Nintendo DSi will be able to play regular DS games from all territories of the world, just like existing DS hardware, titles specifically only for the DSi (we suspect camera-orientated titles and the like) will be region-locked for the first time.

Nintendo exec Cammie Dunaway has clarified - this won't affect standard DS titles, and you'll also be able to use the included Opera browser anywhere in the world too. Apparently the change is due to the DSi "embedding net communication functionality within itself, which will provide net services specifically tailored for each region." New region-specific parental controls were listed as another reason.

All in all, no big deal - unless some uber cool DSi exclusive title never makes it to Europe.