I don't know, the US version makes it clear what you're buying, and even the extra accessories that come with it. The EU Boxes make it look like there's a puppy right in the box, with a tiny accessory DS for it to play with.
The EU versions are cute, but the US version works better as boxart for the console, I think.
PAL, definitely.... Nintendo never does anything clever like that with their hardware packaging here in the states. The only exception I can think of was the Metroid Prime GameCube bundle (the outer sleeve with Samus' visor).
I sold someone on a Teal Nintendogs preorder today. He was looking to get the system and the game anyway, and didn't have enough money for a while (he was trading in some games to help save up). He was pretty excited about it.
That first Euro one would have been perfect with if a real DS was on the floor next to the puppy's head instead of a stock picture of the system with a 'white glow'. And that teal DS is slick.
Edit: I almost missed the top of the box. This box is even better than I thought. If NOA even had half a brain they would scrap that current box and go with the PAL boxes.