To be fair, the technology is really fascinating. Virtual objects throwing shadows on the real environment or generating a virtual face in realtime is stunning. But on a practical note, does this keep your face from getting sweaty? Can you wear glasses comfortably? Can you change light seals when they get dirty?
Nevertheless this is in effect just a glorified monitor, but will certainly cost several times more. So I really can't imagine compelling use cases. Especially since you can only use it with other apple devices.