There's this interesting study from the university of Utah which asserts that we're in deep trouble. The study seems pessimistic about action on global warming - claiming that economic growth is correlated with energy use, which is correlated with carbon dioxide emissions. And therefore, nothing short of a full-scale-economic depression will save the world from a climatic armageddon (if I may use some rhetorical flourishes).
The author's main contention is that all the gains made out of efficiency will be reinvested and will result in further economic growth. This will result in the a sort of grotesque law of conservation of CO2 emissions. It's just like people with high mileage vehicles tend to go on longer drives than the SUV owners.
The authors model the world as a system which takes in fuel, belches out low grade waste heat (along with CO2) and extracts work (i.e. economic growth). Fascinating analogy.
A standard argument going around liberal circles is that 1-2% of the world GDP invested in clean energy and carbon sequestration type technologies will be sufficient to get CO2 levels under control.
Clearly, the two views are at slight odds with each other. I need to read more.