As the cars hit the track in Shanghai China this week, teams are actually dropping KERS and no more than five are thought to be running with it. Grand Prix Drivers Association director Mark Weber calls the whole situation a "bit of a mess" and wouldn't be surprised to see it abandoned. Both the Ferrari and Renault teams have removed their systems since they add weight and the performance difference is not enough to compensate. The limited testing available in 2009 also makes it difficult to sort out the complicated systems.
Even on road cars, the additional hardware is just one component of the extra cost of hybrids. A significant amount of testing and calibration work must be done to make the systems behave seamlessly. Just adding hybrid technology to a car is no simple matter.