A four hour commute with a self-driving car will be just as painful as four hour communute with a train, except that the cost with the car will be much higher. I honestly don't see self-driving cars changing a lot here.
Honestly, how many people can get up in the morning, get ready for work, go to a car and then just fall asleep again? I guess the percentage of people who will be able to sleep on a commute will be quite low; I know I wouldn't be able to do that.
Not quite. It will be painful from a family standpoint (cannot have breakfast/dinner with family) but commute-wise I would imagine a much better experience:
1. You would be guaranteed a seat. Even when I get a seat on the MetroNorth, the first and last miles are painful -- it still requires a 45min standing subway ride to Grand Central and a 10 minute standing ride from the station to the office. Same thing on the way back.
2. You would be able to sleep in the car since it would likely not require transfers or the risk of missing your stop
3. You could keep all your stuff in your car - laptops, books, etc. The space I have in a NYC subway car is pretty minimal
Anyway, I think telecommuting is going to be the norm pretty soon. Commutes would themselves be rare. They might be a lot longer though.