I found the following video an interesting example of improving robot/human interaction:
The Disney blog has a story on this robot you can juggle with… They used a Microsoft Kinect for the sensors to see the ball and the players. The researchers have also written an academic paper on the research for a robot that can juggle.
What I found most interesting from a business perspective is that some very simple feedback when the ball was dropped made the interaction much more entertaining. Just like when we’re writing the User Interface for an application, these little touches do make a difference.