There is lots of debate on every autonomous car story, including this one, about "is as good as humans good enough", but that's a technical threshold. The real blocker (from my view) currently is and will be liability for "negligence."
If I'm driving and fiddling with the radio and as a result blow a light and kill someone, at most you can turn out my shallow pockets in civil court. The automaker has no liability.
But if the _car_ is driving and blows a light and kills someone, then the automaker can and will be sued because they've got deep pockets. I can see the ads now running during the Price is Right. "Hit by a runaway robot car? Jon from Orlando was awarded $3.2 million! Call Richard Cranium Attorney at Law and get yours!"