You seem to be unaware of the fact that Glass has been around for a few years and nobody cares. I knew a grand total of one person with a pair, and that was amoungst everyone in CE or CS at my university last year.
PDAs / smart phones were around for years before they got mainstreamed by blackberry. People will make this false parallel but nobody wants to wear glasses full time. This is coming from someone who had to wear glasses at one point in his life. Sorry, not nobody, but if glasses (not sunglasses) had a place in fashion they would've caught on. The technology is cool but delivering via glasses is not the right way. I'm not saying contact lenses or some other sci fi thing but they need to utilize and market in a way that they're not expected to be worn full time.