One difference between this and Google Glass is that Glass is monocular. Unless you're blind in one eye, you will be able to see "through" the projection. I a

One difference between this and Google Glass is that Glass is monocular. Unless you're blind in one eye, you will be able to see "through" the projection. I also don't think the representation in the Glass demo video is accurate: I'd expect the images it projects to add to the background rather than replace it entirely. I don't think they could make an "opaque" projection if they wanted to.