I am already thinking about the future generation cars. I visualise my self inside my car with GPS system to which i give order. If i say 5th avenue, then it will respect my command and take me there. i think the petrol pumps would be replaced by the cell store where batteries can be purchased..
i am so exited about the future.
my future car is like car at batman movie
have everything what i want in a car.
stay excited about the future... doubt it'll be that exciting in our lifetimes tbh.
Even if these things do happen, and go mainstream and takeover (which i doubt, because changes only happen gradually for obvious reasons), it'll probably be that gradual that you wont even be thinking about it! 
Who knows what the future will hold, i wouldnt like to guess! More electronics, definately more electronics. Which will increase efficiency, but it will be really tough to fix something yourself without special equipment onboard if you break down somewhere remote.
Also I think we'll see more and more initiatives for Hybrids or pure electrical cars, though changes in that field will go at a slow pace because there is no big need/demand for it yet. So why should they invest in it, except for the occasional prototype to show people they are working on it?
I agree with Briancoit that we won't see any radical designs in our lifetime, maybe only the switch from mainly Petrol to Electric/Biodiesel/other. But I think it will end for us there.
i think future cars will run on batteries or something like solar power to charge and power the engine.
they would hover about 2 feet of the ground and have auto-pilot to take you to your destination.
Here is the ULTIMATE CAR OF THE FUTURE!!!
*3000 Hours litium battery powering the motor. It will take 1/2 an hour to charge it for a full hours use.
*Built in dashboard computer, that has everything incuding:
--Global Positioning System
--Music Archiving System for your tunes
--Video Archiving System for your traffic troubles
--Internet so that you can look at websites of resturants when you are deciding where to go. (and stores and etc.)
--All the computer apps that you want on there
*Built in PDA so that you can voice dial calls, make appointments, go throught your address book, check appointments, check your to do list, make shopping lists, and organize things.
*An awesome sound system
*Heated and Cooled seats
*Plenty of Space
*Many ways to add extra features.
That is the ultimate car of the future
