Question for David

With the current state of the economy, very few people are buying new cars. And those who are buying new cars are probably much more concerned with the price and economic efficiency of the car rather than the effects the car will have on the environment. Even if these new diesel cars get more mpg and are environmentally friendly, what is the likely-hood of their success in this economy? If these cars cost more than a car that takes regular gasoline, plus the increased cost of diesel fuel, then why should anyone be motivated to purchase one?