In reply to your profile comment, there's actually two factors. One being that the 3DS is, technologically speaking, more powerful than the Wii in terms of graphical power... Although don't quote me on this, it's just what I heard way back when the specs were first released.
Second, yeah the lighting was re-done, textures were fixed up, and a new shader was made called Dynamic Shading or something like that (it makes the shadow actually look like a shadow of it's object instead of a circle). Honestly though I don't really care too much for the graphics or specs, the game isn't the best looking out there by any means.