Are your hands tired of the Wii fishing rod? This is still nonsense. Apple is on guard of the health of earthlings - now you will move with your whole body.
This “input device” “recognizes” your entire body, not just your finger on the screen. They write: "A silhouette can contain more information than the position of the stylus or even a keystroke." Apparently, this is a prototype, but the prospects are sky-high - take a look at how Steve types. And you can probably choose a set of movements: you want to - disco, you want - wushu.
PS: There is a big picture: img511.imageshack.us/img511/9868/idancetq5.jpg