Forget about the technology of the machine, assume the boffins will solve the technical issues and produce a "driverless" drone capable of carrying 180-250kg payload.
Where is the market? Think about your own travel habits. Work to home. Home to work. Home to shops. Shops to home. Home to restaurant or entertainment area and back. Now, how many suburbs could accommodate a craft landing within walking distance of your house? Sure, your local Westfield can give up a hundred car bays and fence off a 60m by 60m landing pad but as said above what about the CBD?
The front runners in this should be parcel delivery by autonomous drone, are they near? Not really. When they solve the parcel delivery issues then the air taxi may be closer to reality.
Probably more like this Neville, not tilt rotor...
