If you notice, they are mostly making hybrid SUV's. This is an easy way for them to meet their CAFE requirements- in many cases they are paying penalties for having vehicles not meeting CAFE standards. It does nothing for overall fuel economy. If they cared about fuel efficiency, they would be pushing small cars.
There are off the shelf technologies that could make more efficient cars, and cars do use them, but there are few cars that put them all together. Many Japanese engines already have variable valve timing- for instance Honda or Toyota engines. A few also are lean burn (Civic, Insight). The integrated starter motor is used in several European cars and also is the basis for the Honda IMA hybrid system (it's actually more of an "advanced" starter motor generator, with generative braking capability). VW-Audi also has a highly efficient direct shift gearbox, which is essentially a computer controlled manual transmission.
The bottom line is it will take higher fuel prices to motivate people to change. You are starting to see that pressure with gas averaging over 2.12 per gallon, but it will take higher prices to really push people. Only by ending subsidies to the oil industry and forcing drivers pay the full costs of using the roads will people make better choices. Of course, higher gas taxes are politically hot water.
