It is going to take longer than expected to have a perfect driverless car but when it is here the takeover is going to be extraordinarily quick.<p>I believe the regulatory hurdles will actually go the other way -- suddenly it is going to be very hard to be a human driver on a public road. It is the regulations which will force human drivers from the road, not self-driving technology. Someone can provide a better analogy than I can, but it would be the equivalent of trying to hand deliver a packet rather than send it across the internet.