Once the animated sumo face is generated, you can then have a little fun by slapping him (or her) around a little bit with your finger. Watch the face react to the abuse with various winces and frowns. If you speak, the application will play back what you said in a typically deep sumo voice.
SumoBooth comes with some social functions as well, like the ability to take snapshots and video of your new sumo face and then share them via Facebook, Twitter or YouTube.
The app will be featured at MotionPortrait's booth at Macworld 2011 for those who want to check it out. If you can't make it, have a look at the following video posted over on Appbank (Japanese).