I love people come up with worst case scenarios, and then use them to argue against a new technology
Do you think, perhaps, the car will be programmed to not consider the pavement, or other pedestrian areas, available to drive upon, even in an emergency.
Also, as I understand it, the Google cars in California have driven 100's of thousands of miles, with no accidents - which is a significantly better record than human drivers.
The likelihood is that the computer driver will be a better/safer driver than most humans.
For the people who say they like driving, and would be bored sat in a car driving itself - well, consider those numerous morning commutes, where you could let the car drive through all of that rush hour traffic, whilst you do other stuff - once we get passed the point where a 'driver' has to still be capable of controlling the car and trust the computer enough, you'll be able to do all those things that stupid drivers currently do, only legally and safely (You know, those people chatting on the phone, reading the newspaper, eating breakfast, doing their makeup - I see an example of some form of idiocy behind the wheel every single day)