I don't think consoles will be region encoded anymore, the PS3 isn't and I don't the the new PSP is and my DS can play both Japanese and Europe carts and I didn't mod it in any way. Region encoding for consoles doesn't make sense anymore, if you go to a 3rd world country the consoles aren't any cheaper, in fact they cost more than they do in the US or Europe. Games are cheaper, a little, but you won't want to buy a game that isn't in your language anyway, so you're not going to go to Mexico and buy a game in Spanish just to save a few bucks.
The only reason to have region encoding is for countries like China, middle eastern countries, and other countries like them that control media to the point that their people have no idea what is going on in the rest of the world. Nintendo, Sony, and Microsoft make special consoles for countries like these, unmodded they won't play any game that doesn't have their region encoding. Surprisingly all the countries that have to worry about this stuff don't speak a Latin based language so they have a really hard time playing English games. I don't think any of them can read Japanese well either.
I still think movies played on these consoles obey the region encoding, which is pointless also, China should have a region encoding and middle eastern countries should have their own and then the rest of the free world should be able to watch whatever they want.
Anyway, I can play other countries carts on my DS and it has 6 languages, and I know Brazilian PS3's can play US games unmodded where the PS2 you had to buy a modded console. I think you'll be fine if you buy a ultra huge DS from Japan, I think region encoding for the free world is going away.
The only thing you need to worry about is if the country uses a means to get data on the device wirelessly that is not compatible with the wireless means in your own country. That and the wall socket.
