Until this spring, the Toyota Camry Hybrid was the only mass-market, four-door full hybrid sedan sold in the US. Then Ford introduced the 2010 Ford Fusion Hybrid, and reporters have been comparing the two ever since.

Perhaps to keep up with a newer, younger, hotter rival, the 2010 Toyota Camry Hybrid has had a bit of cosmetic surgery for the new model year. Toyota has given it a new grille and bumper, a restyled lower air intake, and updated fog lights and rear tail lamps.

Inside, the meter cluster has been enchanced and the cloth seats have a new material. And, all four windows now have automatic up and down (why isn't this standard on every vehicle, please tell me?).

The changes are minor, and subtle, but they give the car a fresher appearance. The drivetrain, however, remains unchanged: A 147-horsepower, 2.4-liter four-cylinder gasoline engine is mated to an electric motor that adds another 40 hp.

The Hybrid Synergy Drive system operates like a continuously variable transmission, constantly adjusting engine speed and electric power for maximum fuel economy.

The Camry Hybrid can run solely on electricity, but only below 30 mph and for little more than a mile, if conditions are right. The Fusion Hybrid, in contrast, can run in electric mode up to 47 mph, which turns out to make a major difference in how much the gasoline engine stays switched off.

And the mileage ratings reflect it: The EPA rates the 2010 Ford Fusion Hybrid at 41 mpg city / 36 mpg highway, while the 2010 Toyota Camry Hybrid lags at 33 mpg city / 34 mpg highway.

Testing last year's 2009 Toyota Camry Hybrid, our reviewer Marty Padgett liked the "adequate acceleration and great fuel economy," the smooth ride, and the comfortable cabin.

He wasn't so thrilled about the dull styling, the compromises to handling with the added weight of the hybrid system, and the difficulty he had keeping the car at a steady speed without using the cruise control.

The 2009 Camry Hybrid still got a respectable 8.2 points out of 10 in our review, but the 2010 Ford Fusion range (as a whole) got 8.8. We think the battle of the midsized hybrid four-doors will be one to watch in 2010.

2010 Toyota Camry Hybrid

2010 Toyota Camry Hybrid