So is the congestion charge working?

Not according to this research from Direct Line, reported in Money Extra.

Research "reveals that 1.2 million (16%) motorists who intend buying a car over the course of the next year will purchase either a people carrier or 4X4 'Chelsea tractor'. In fact, motorists are four times more likely to buy a less fuel efficient vehicle than the more environmentally friendly hybrid or 'eco' cars this year."

"The research also reveals that despite the London congestion charge, 27% of Londoners are planning on buying a car in the next year, compared to just 20% of those living in the Midlands and 21% of Northerners."

Looks to me like the congestion charge makes absolutely zero difference to the purchasing habits of the Islingtonistas. But then again, banning plastic carrier bags is far more important for the future of the environment, isn't it?