Google Glass is Google's attempt to replace the computer in our pockets, i.e. the phone, to a computer that we can wear. It is a hands-free head-mounted intelligent device that can be worn as eyewear. People are already wearing them while driving which is illegal. Cecilia Abadie, from San Diego found out the hard way. She got ticketed while driving with her smart goggles on.
So why not integrate it into the car system. Well, leave it to the German carmakers to pick up the latest and fanciest gadget and come up with an application for it in their cars. Mercedes is developing a new navigation system that utilizes Google Glass with a voice activated interface in one lens. The Google Glass will be able to guide drivers to their cars, transfer a destination address to the vehicle's navigation system and back to the Glass allowing a walking directions to your final destination.
Drivers will be able to access the Internet and many other applications without distraction. Normally you need to take your eyes off the road and look at the car console screen, but with the Glass, your line of vision will remain on the road.
The Mercedes Benz "vision" is a few years shy from making it into any of their current models. The Glass is not released to consumers yet. But Mercedes is definitely trying to be ready just in case it becomes popular.
Mercedes, and many other luxury automakers, are approaching technology differently. They are adapting new technologies quickly and building new models that are capable of integrating new gadgets. You know you could never predict what future "rich" nerds will be into.