In that respect it's no different from the hundreds of security cameras most of us pass by each day. If you're doing something in the presence of someone else's view, and you know they're pointing a camera of any type at you, it's hard to argue you have an expectation of privacy.

It's really hard to point at Glass and say it's materially different from the broad array of recording devices already out there. If you're someone trying to avoid being recorded, those are a much bigger problem - they're pervasive, generally have better viewpoints (can see more total area) and often have built-in illumination as well.