I waited for the Leap Motion for 8 months. Finally today I tried it, I have to say I think it is fun and also useful in certain activities, not only educational and fun.
This type of interface opens new scenarios, to date the GUI for PC take their cue from the real world as windows, drawers and disfigures them in the virtual world, the drawer of my bedside table does not open by double clicking above, as I do not make the window disappear by pressing a button. I wonder if the leapmotion, (and similar devices that will be), with the new (in the virtual world) way of interaction, which is closer to those we use in the physical world, does not lead to rethink user interfaces and the user experience more modeled on the physical world (in case opening a directory pulling and not pressing).