I'd actually say that the US needs a CTO, who would be responsible for identifying the most promising technologies to subsidize the development of. Someone who can look at the range of technologies that are under development, and decide whether it makes sense to go for more efficient production of renewable hydrocarbon fuels for cars and fuel-efficient hybrids, or whether we'd do better to produce more electricity in the midwest, transport it as compressed hydrogen gas, turn it back into electricity in the high-population areas, and drive plug-in electrics. And are we going to use enough more oil to make it worthwhile to put research into cleaner and safer processing, or should we focus on not using it in the first place? OSHA, the EPA, and the DoE each have their own priorities, and there isn't anyone in the position to find a balance between them and get useful things done.
On the other hand, the government needs someone to fix the government's information technology problems, which is an entirely different job, and seems to be what Obama's looking for. I'm not sure why this post isn't called "Secretary of Information Technology", actually, which would be more in line with other executive branch government posts and distinguish clearly between the two possible job descriptions.