The key experiential question of Google Glass isn’t what it’s like to wear them, it’s what it’s like to be around someone else who’s wearing them. I’ll give an easy example. Your one-on-one conversation with someone wearing Google Glass is likely to be annoying, because you’ll suspect that you don’t have their undivided attention. And you can’t comfortably ask them to take the glasses off (especially when, inevitably, the device is integrated into prescription lenses). My best friend was an early adopter of the iPhone. It was so new, so entrancing at that point that I had to endure about a year of him gazing down at his cupped hand during almost every conversation. Those conversations were some of the most infuriating I've ever had. He's promised to be an early adopter of Glass, and this time I think I'll make a point of telling him to take the damn things off before we hang out.
As much ad I hate that behavior, I know I fall into the same trap when I get a new phone. I make a conscious effort to not do it after I realizes 90% of the people at our comp sci socials were face down in their devices. It's one of the reasons I've stayed away from social networks for so long: I don't need more reason to be constantly connected to tech.