Tesla = big money. Big money = big batteries.
Ever wonder how much it costs in terms of batteries to give a Prius an actual battery-only range?
$4995 for 360 pounds of batteries that can go 15 miles.
So... 40 miles, say $15,000 worth of batteries at over 1000 pounds.
GM has to get that range out of batteries that don't weigh 1000 pounds, or the car won't fly. And they have to do chassis development... and testing and mass production... etcetera.
Tesla, on the other hand, took a Lotus Elise, stripped the drivetrain, shoehorned in a whole lot of
expensive Li-Ion batteries and made a sportscar that costs a hell of a lot of money. (I've always held that the Tesla, intriguing and appealing though it is... does not go over any ground not already covered by previous electric sports cars...
http://www.venturifetish.fr ...it's just that it does it at a level of finish and a price point that's better than the incredibly limited Fetish.)
Honestly... GM has gone it alone with electric-only vehicles and now with electric-charge-depleting hybrids for decades... they did as much as they could do with the EV1, but the market wasn't there to support them... how could they sell electric cars when people didn't want to pay for them?
Much as I don't care for many GM products, I seriously hope the Volt works out.