Nevada (the first jurisdiction to officially allow self-driving cars) has, in fact, added an exemption to its cell phone ban for that type of vehicle.

The NTSB would probably love if autonomous cars became the norm. The rate of accidents would probably go through the floor, since most drivers suffer from a bad case of survivor bias. They actually talk about requiring more automated safety features (like collision detection for commercial vehicles) in their report.

You wouldn't be the "driver" then, would you?