Ninokuni may very well be the most beautiful DS game so far. I tried it for a few minutes, I'm glad I could play the demo. I'll give some impressions for those who can't or don't want to play the demo.
Gameplay-wise, the game feels a lot like any other normal turn based RPG. You run around a world, collecting treasure, talk to people, or fighting monsters. I can tell it's an extremely solid formula, but it's not very innovative or anything. Battles are random, but they don't happen often enough to get annoying. Your characters get noticeably stronger when they level up, so it seems like a nice balance. The game isn't easy either. I've only beaten a few enemies and couldn't get past the first real boss yet. I clearly need to level up a bit more. In battles, I've gotten 3 characters so far- Oliver (the boy), a little fairy with a lantern hanging off his nose, and a little creature with a sword whose head looks like a horned orange. The sword creature seems to be the strongest physically. Oliver can cast useful healing spells, and only wields a tree branch at first (assuming he gets better equipment later).
There's a mechanic where you can draw on the touch screen to create symbols that do certain things. One such is a door, which leads you into Ninokuni, the other alternate magical world which you explore in the demo. The other symbol I learned from a giant talking tree and lets you summon the little sword wielding knight. I assume you learn more symbols later on. This seems to be the only time thus far where the touch screen is required. You can move and select things with either the buttons or touch screen. I only used the buttons, but the touch screen worked pretty well if you like that kind of thing.
Graphically, the game is absolutely stunning. Hiring Ghibli to do the animation and graphic designs payed off incredibly. Even in the small demo, the game is full of full motion video. Not that grainy kind full of artifacts either. It's smooth as silk and clear as crystal. The environments are hand drawn it appears. Most of the time, they appear as flat, non 3D, and already spectacular at that. There are environmental effects like dynamic lighting (like go into the shadows and Oliver appears shaded) and flowing water. Characters are 3D cel shaded models apparently. They actually blend quite well into the world though. In some of the cutscenes, the environments actually change to 3D to provide for more dynamic camera angles that 2D can't handle. It's something I give them credit for that I've not seen before. Changing from 2D to 3D provides a really nice balance between exploration and story telling.
Surprisingly, the sound is about equal to the graphics in terms of impressiveness. There seems to be a fully orchestrated soundtrack with gorgeous compositions, many of them with violins. It creates a great magical atmosphere. Apparently the music is one of the major reasons they are using a 512MB cartridge, and it really pays off! There is also a ton of voice acting. Probably at least 85% of the demo is fully voiced. It's very charming, although I can't understand what they're saying.
Coming away from the demo, I wanted to know more about the story and gameplay. The game is a technical marvel. One of the best looking AND sounding game on the DS. It's flawless presentation-wise. The demo clearly wanted to express how amazing it looked and sounded. The gameplay will at least be a very solid turn based RPG, but I didn't get a feeling that it was much different from any other RPG. Clearly, the story will be much more developed when it releases. It's too early to judge what the gameplay and story will be like, but this game is definitely magical and absolutely charming and gorgeous.
If this doesn't come out in the US, someone's going to burn.