There's also an article about this at heise.de. The guy is an unknown hacker at the hacker congress 23C3. It's heavily discussed if it's a fake or not. Some said that they saw that this was not a video played over a laptop, but that the Box was connected via a circuit board to a laptop. They don't know if it's "only" a shader-hack of the graphic display, or if he really ran a code. The bouncing of the played screen combination points to the expectation that it's the latter.

But they also say in another article that the Wii has high potential as hacker target.