I'm sure the main reason is that price of diesel fuel here is not that much cheaper than gasoline.
and also... I agree that a lot of people still like that high strung sound of a high revving gas engine (Ferrari for example).
I must say that these cars should stay the way they are :p I'd hate to see a Ferrari with a diesel engine hehehe..
However I really think that SUV's are the best candidate for diesel engines. Mid-size passenger cars as well...
I think cabs should be diesels