That is so cool. One would have to have good balance to use it, but it looks like more agile wheels. Maybe this will move over to other kinds of chairs. Speaking of chairs, it puts a person at a closer height to standing people and takes up less space. Again it won't work for everyone but it's a good innovation in design for those who can use that option.
(Might be more awkward at a table or concert, though, but at an event they often tend to stick wheelchair users in the back anyway)