One thing that is noticably absent from both the product description and the video is the runtime of the light between charges. It is no accident that they don't mention that, so I'm betting it will be pretty short, perhaps in the range of 15-20 minutes on low. That might be fine for many uses where the charger would be accessible, and could be handy around the house.

In any case I'm interested to see how this technology develops, it certainly has a lot of potential.