OK, heard back that I have permission to talk about it in a limited way and no photos of the windows themselves....
Yes it works, and it seems to be an adaptation of the Daimler concept. The windows had to be replaced and Tesla installed various sensors inside the car to measure temperature and UV ingress; I have no idea what it all costs but I'm told that after the test they will remove the sensors and I get to keep the windows, in return I do have to keep a weather log for a couple of months (oh the hardship! :wink
The magic sky windows operate on a slider bar on the touch screen so you can adjust settings to your personal preference depending on light/sun conditions. The software shows it as an extra tab and it's not all finalized yet, it looks like the pano roof slider but doesn't show a side picture of the car yet. I'm waiting on approval to show a photo of the touch screen.
And yes, I believe there are a couple of other folks beta testing it in hot climates.
It's probably branded for display at a trade show. Maybe it will be at Teslive?so then the question becomes why the heck would they plaster the name of this in-testing feature all over the door sills of the test vehicle? Seems crazy to advertise that they're testing it.
The least believable part IMO was TEG (of all people) not being able to find the obvious keyword in the name on the side.
Looks like the cat not only got out of the bag, but the beans got spilled too.