I usually trust Ars, and they said
However it works, HoloLens is an engaging and effective augmented reality system. With HoloLens I saw virtual objects—Minecraft castles, Skype windows, even the surface of Mars—presented over, and spatially integrated with, the real world.
It looked for every bit like the holographic projection we saw depicted in Star Wars and Total Recall. Except that’s shortchanging Microsoft’s work, because these virtual objects were in fact far more convincing than the washed out, translucent message R2D2 projected, and much better than Sharon Stone’s virtual tennis coach. The images were bright, saturated, and reasonably opaque, giving the virtual objects a real feeling of solidity.
Through it all, the 3D effect was thoroughly convincing. The system felt very low latency; as I moved my head and walked around, the objects retained their positioning in the real world, with the castle, for example, never becoming detached from or wobbling around on the table. While Minecraft of course falls some way short of having photorealistic graphics, the melding of real and physical nonetheless felt convincing.
That said, the version they could try was more clunky than the presented on stage… AND it was tethered to the ceiling (power?) AND it was tethered to a “neck computer”. And some other articles mention the fov isn’t that wide, so all it’s done in a “window” in front of you, nor you could pin virtual objects on reality, so I suspect the MInecraft demo was very set up for that particular room. Could it work if you would do it in another room? In theory yes, in practice I suspect it’s still too green.
Microsoft is doing a great Research job with these technologies, but don’t expect it to have it really working as they staged until 4 years or so, as you can’t solve the computing and power needs just clasping your hands. And the most advanced stuff from their concept video will be still further away.