Now we know why Google Glass quietly went away...
I think Microsoft is getting right everything that Google got wrong with Google Glass. Google Glass, other than being the next big thing for techno-snobs, didn't really have a lot of usefulness. It was the next big social networking device.
This device, on the other hand, is a device you use at work. You won't care if you look like a dork while you are sitting in your cubicle, as long as you are getting work done. And I can see a million different business uses for a device like this, such as having technical documentation and models ready when the user is out in the field trying to fix machinery. While wearing the device the user can still see the real world, it is just overlaid when something is useful.