[grudk]

Lots of variables, as noted above: economy and when it recovers, oil prices/reserves, technical innovation, govt legislation

That said, my feeling is that we will have fossil-fueled cars dominant for a while yet, maybe 10-20 yrs. Engines will get smaller, more efficient -- lots of turbo/supercharging. Cars will get smaller on average. Large displacement engines for personal use will increasingly rare. Conventional supercars will disappear, to be replaced by more exotic/innovative creations.

After 10-20 yrs, electric cars dominant

Detroit will still be around, but the brands will be shuffled and condensed. I think Cadillac, Jeep will be here. Saturn may go the way of oldsmobile. Volvo and Saab may go back to Swedish ownership. Some new brands will emerge.

I think it will all be very interesting, though i expect we will see our old porsches legislated off the road at some point, or perhaps licensed for limited 'show and display' use