Sorry, it just seemed necessary to write that out twice.
Fast Company caught up with one of the researchers behind this feat, Raffaello D'Andrea , for a quick exchange:
FC: When did you first realize that you were bereft without juggling robots?
RD: A while ago. Which is why we built the Blind Juggler  several years ago.
FC: Why is it important for our future robot overlords to have court jesters who can juggle?
RD: It is likely that the court jesters will be human, we are easier to maintain.
FC: Do you have any plans to program sword-swallowing or fire-breathing robots in the near future?
RD: Please don't give our future projects away.
FC: In all seriousness, why is solving the problem of robot juggling important to robotics, AI, virtual vision, and the like?
RD: The approach in our research group is to pick difficult dynamics and control problems, and to develop the algorithms necessary to solve them. Controlling an unstable vehicle in three dimensions to intercept a ball and to direct it to a desired location is a challenging problem. The algorithms and know-how that are developed in solving these types of problems transcends the specifics of the demonstration. Case in point: I am one of two technical cofounders of Kiva Systems , a materials handling company that uses hundreds of mobile robots to move inventory in distribution facilities (Fast Company actually covered  Kiva some time ago, when we were a fresh startup). Many of our first hires were my former students involved in Robot Soccer  and other projects with no apparent utility.
But most importantly: why must everything have direct utility ?