What Google is hoping for is to tease us into wanting something, that no one has asked for.
Google is not alone in this historically.
Let's step back a decade, when we were all told that Microsoft (by Microsoft) had the biggest R&D budget in the world.
What products came out of that R&D? ZERO.
Apple on the other hand spent years developing the iPhone with iPod profits and never let on what they were going to reveal. What happened? A mobile revolution.
Google is telegraphing R&D to try and leapfrog Apple in the public mind while having no viable consumer product in the pipeline much less on retail shelves. Thats tantamount to product suicide.
I think Glass or something like glass could be important, but I think that Googles approach to pushing alphaware in front of the masses, will, if it really is viable force google to play catch up to Apple or someone else once again.
Google has never, not once, in its history, had a successful launch of a hardware product.