I find it ironic that there is talk about buying a new car with more bells and whistles in thread talking about how more efficient cars could help. Getting rid of as many bells and whistles as possible would reduce both the weight of the vehicle and the internal power demand of the vehicle which helps the efficiency.
There is lament about why nothing is done. Well, according to any new data the production of CO2 pretty much has to stop ASAP to have a hope in hell of reversing things. For North America, if you tell people they have to give up their houses to live in new high efficiency apartment building, give up all their gas powered toys and give up their larger sized SUV's and trucks for small, most likely shared use, electric cars then you'd simply get voted out of office.
For North America, a carbon tax that is high enough to be useful would push many homeowners out of the place they live in because they wouldn't be able to afford the heating bills. It would make it impossible for most everyone to use fuel to commute or travel more than short distances, so again that means moving a lot of population around close to where they work. But then, there is no way a carbon neutral planet can support anything close to the industrial level that currently exists, so a bunch of that has to go away somehow. Overall, major upheaval which again gets you voted out of office for trying to implement such things.
On the plus side, it will push people back towards simpler times, doing things like hanging out and having a community dinner with neighbors in the evening outside, instead of eating alone in your house with the AC on while staring at your cell phone screen.