@Chickenhouse:
The liability issues will be ironed out, well before any of these things become practical, because the same issues arise with autonomous road vehicles. There will be a framework of laws, regulations, and insurance that won't be that difficult to apply to private autonomous aerial vehicles.
Autonomous cars will be quiet though, and these things won't be quiet. Not as long as pushing air from a rotor is the lift mechanism. That's why I think noise is the main barrier to seeing this happen.
It will limit Amazon (and others) working on drone deliveries too. I can handle seeing Fedex and UPS trucks making daily deliveries to other houses in my neighborhood. They don't disturb the peace. But a daily squadron of delivery drones, making the kind of racket you would need to deliver some of these heavier packages? That's something else again. You can bet there will be resistance to it. The technology just doesn't scale up without serious noise as a side effect.