The Leap has been around for a good while, the Occulus Rift has been around for a good while, and 3D Laser Sintering has been around for a while, along with every other technology they're using for this application.
Also, I believe they're the wrong people to use it. Making the feedback involved visual instead of mathematical/geometrical has it's applications (quickly looking through the design), but it'll still have to be made to precise tolerances, and that's an engineers job, not a sculptors.
On the other hand, it's perfect for sculptors and designers. If their setup is considerably improved in resolution, designers can get very fast visual feedback, and trying out things suddenly becomes very cheap. Architects can mold parts of their buildings, your furniture can get those last brushes before it's milled out, and your phone can be molded to "just perfect".
But this isn't a Musk thing, nor is it an Iron Man thing, the idea has been floating around for a good while, the tech is there, they just went ahead and made it. That's not groundbreaking, and it isn't revolutionizing manufacturing.