From what Ricky said on Inside the Magic...
There are 4 games running with one more in the works. One is to create a landscape by moving your arms around to create mountains, trees, ect... The second is a racing game where you race a bird through scenery by leaning around and compete with other people playing. The third is a blob game where you just play with them and you can pop them and stuff by moving your arms. The last game has different scene with a different theme (beach theme with beach balls, winter scene with snowmen and snowballs, a dessert scene with tumbleweeds, a canyon with boulders, and a desert island with coconuts.) You can just play around with that for a minute, and then the scenes network together and you can throw snowballs (if you have the winter scene) at other people in their scenes and interact with them.
Edit: when the games are not going, there either is a static image, or there is a slideshow playing.
Again, all info from Ricky.