I'm going to make a prediction....
The only people who wear Google Glass all the time will be those twits who also walk around with a bluetooth earpiece attached to their ear lugs. You might wear Glass for a specific task but the idea that you will have it on your head while you sit with your mates in the pub is frankly ridiculous. People spend a long time on their faces, hair and clothes - even those who work in IT - and they are not going to take to something that makes them look like a Star Trek extra. And that's before we even start to talk about the inevitable weight of these things. Did anyone ever try on the Oakley sunglasses with a built in MP3 player? If so, you'll know what I am talking about.