Right. I'm a bit surprised that Microsoft Research is so hipster-heavy.

No, its a hipster thing.

All of the human subjects (at least 6 subjects) whose hands are being tracked are wearing mirrored sunglasses, and fashion considerations are significantly less likely to cause "100% compliance" than safety considerations are.

This was discussed on /r/oculus and it was suggested that Microsoft could be overdriving the infrared so it's for eye protection

Anything with that level of accuracy would be using some kind of high-power Y-Ray (like X-Ray but more penetrative) laser. You usually only find that kind of thing in space to protect astronauts from the slightly more powerful Z-Rays (from aliens? Not sure...). You would definitely need to protect your fragile eyes from Aviator glasses. Additionally, half smoked cigarettes hanging from your mouth can help protect this orifice and a leather motorcycle jacket can be worn to protect vital organs.

You should can only expect a large corporation with plenty of funding to have access to this kind of technology (the safety gear I mean, not the lasers which are relatively cheap). I hope that answers your question. My source is Bill Gates, I swapped him my Dinosaur in exchange for three company secrets.