I went for a nice bike ride yesterday with the kids, and shot some video on the Glass while on the bike.
I had a very interesting feeling while I was riding and recording. I could hear a car coming up from behind, and instinctively looked up in my rearview mirror, only to find the view was just a capture of my forward view, slightly offset. Very strange. I wonder if a similar phenomenon would occur if the Glass display was positioned below my field of view, instead of above.