Why is that, do you have some particular use case? If not, are you sure you'd keep doing it after the first couple of days?
Here's a thought for you. I wear glasses, I have for every day of my life for more than two decades. If Google offered me almost indistinguishable glasses that work just fine but also have a HUD that shows me things I care about (Google Now is the first step towards that) then how could I say no?