Believe me, this is something I've been thinking about. Hopefully by year's end I'll have some integration like this. Not that it takes that long to develop, but I have a lot of other things on my plate right now.
Sounds like a good idea on the surface of it, but I think most Google Glass owners would probably take it off during a movie in the cinema. It would probably feel slightly distracting with such a big screen in front of you. Glass does sit a bit above your right eye, but not to the extent that it's completely unnoticeable.
They should implement something similar, given the watch concept is significantly less intrusive and… bright.