We'll have autonomous driving capability in every car, I have no doubt. But driverless cars? Not in our lifetime I suspect. Google cars are a nice PR exercise for the company, but nowhere near ready to be released in the wild. What possibly will happen is that by the time we have the technology, cars will become obsolete as mode of transport and we'll have better ways of moving around, which will render driverless car technology obsolete as well. So it may never get implemented.