London's Docklands Light Railway has been driverless since it opened in 1987 and in 2013 carried 101 Million people, its accident rate is way way less than rest of London Underground with drivers attached.
The docklands light railway has exactly one variable: speed. The amount of variables involved in flying an airliner to destinations around the world is orders of magnitude higher - there is no sensible comparison.
Reading the Boeing service bulletins in the flight crew operating manual of the 777 I fly is enough to convince me that I wouldn't want to ever fly in a pilotless aircraft - I personally don't think it will ever happen, even though it is technically feasible.