But it could also be a major altering of norms. Are women comfortable with the idea that any guy looking at them on the street can capture their image?
It seems like the biggest difference is that if a ton of people were wearing these all the time, police couldn't tell everyone to turn them off. If they looked like normal glasses, they wouldn't even know.
The difference is speed. You'd always have a camera aimed at whatever you were looking at. If you saw a mugger grab a purse, you might not have the presence of mind to fumble with your phone, but you might be able to press a button or say "take picture" (or whatever). I'd imagine that a decrease in response time could be a real deterrent.
I know there've been spy cams forever, but I'd argue that merely owning one (let alone openly displaying it) would mark you for suspicion among a lot of people and I don't think they're widely used. I'm not saying it's the end of the world, but there are some new privacy norms that will be established if these are to take off.
With social networks and internet, managing one's "online identity" and privacy is increasingly important. Everything you say online might be stored and retrieved later. It's hard enough when you are an adult. But what about kid/teenn, who is still trying to find his identity, and might say things that he regrets later on?
What happens when real life is logged?