I think I can see what google is going for. Their development in terms of products and services seems to be filling in the small pieces of a big puzzle. You use google services at home, on your mobile....the most important of those things can be displayed on the glasses.
Phones can be ignored, but if you're wearing these glasses, it'll be hard to miss a call or a reminder.
Maybe they'll also add gesture recognition, so you can make gestures with your hands to give certain commands.
It can find applications in the augmented reality areas too, maybe shopping as well?? You scan a QR code, and it tells you the specs of the product you wish to purchase, offers etc.
Its good to see a company trying to do something totally different for once.