Autonomous cars will first roll out to robo fleets. This is inevitable given the costs and opportunities. On the cost side. autonomous vehicles will be very expensive. To amortize the cost, you're going to need a high utilization and revenue. Robo fleets can do that. On the opportunity side, there is a lot more profit in transporting people than there is in selling vehicles. A lot more.
Individuals will have to wait. You're right about lots of Volt drivers talking about wanting to buy or lease an autonomous vehicle, but they also complain about a $40K price point. They'll have to be prepared to put a 1 or a 2 in front of that to get one.
Personally I don't think you need an autonomous car. Something that works on interstates, like SuperCruise, should work for longer trips, either pleasure or commuting. For shorter trips it's not a big deal to steer. All the other safety features like emergency braking and blind spot warning and lane keep assist should keep you safe. I never use ACC for local driving, only for longer trips.