As cool as the idea sounds, I'm sceptical of the real life usage scenarios. It would be interesting for the first few days, but after that I think it would be simply annoying. Just think about getting notifications from FB, Twitter and other apps all the time - with mobile phone you can just ignore them and check later when you have time, with Google Glass they would be thrown right in your face. Not to mention ads, which I'm pretty sure will come sooner or later, and I won't even start about the privacy. Also, watching the Google Glass ad[1] I was constantly switching my focus between the display and the actual view - in real life it's a great way to have an accident. And one last thing, from the ad I've got the impression that the main use case is sharing your life with others, which I think is already at ridiculous level (like people sharing what they ate for dinner) - now it'll be even more ridiculous by people showing off they entire day (me walking in shopping center, me riding on a bike, me eating and so on).