Word is that American carmakers and -buyers are now "quietly turning" (whatever that means) toward using turbo-powered cars. Turbo-charging involves re-compressing exhaust gas back into the car's cylinders, which gives an engine more power and efficiency, which lets you use a smaller, lighter engine, thereby increasing efficiency further.
Of course, turbo-charging has been around for almost a century, and according to the L.A. Times, the U.S. car market is only really coming around now because turbo was seen as a fiddly tweak for little, zippy Euro cars, not big, burly American models. And Detroit wonders why they have to give cars away...