Everyone has opinions. But if you had to wrap up what's happening in green cars today by naming three trends, what would they be?

The ever-eager publicists at auto-classified site AutoTrader.com sent us their list of three changes in the world of eco-friendly vehicles. We've reproduced them below, along with some commentary of our own.

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"In the past, the selection of eco-friendly cars was limited, forcing consumers to choose from a handful of options," said Shawn Tucker, auto analyst at AutoTrader.com. "Today, manufacturers are catering to everyone, and the definitions of [green] vehicles are changing."

So their three trends are:

"Green" gas mileage from conventional cars

Lighter-weight materials and smaller cars let makers squeeze out 35 miles per gallon or more from conventional gasoline-engined cars, without the added cost of a hybrid powertrain or a clean diesel engine.

Examples: 2011 Ford Fiesta, 2011 Scion iQ, 2011 Chevrolet Cruze, 2011 Fiat 500, Mini Cooper

Our comment: Absolutely. We write, over and over again, that smaller and more efficient engines will greatly raise the fuel efficiency of standard gasoline-powered cars. Hybrids, plug-ins, and diesels will have to chase a moving target.

Turbocharging: It's not just for performance any more

Once, it was all about the extra horsepower. Turbocharged engines were known for their performance. But now, many carmakers are using turbos to increase gas mileage by getting more performance out of smaller engines.

And consumers who see turbo models should ask. "Is that an efficiency turbo or a performance turbo?"

Examples: 2011 Chevrolet Cruze with 1.4-liter engine, any Ford or Lincoln model with an EcoBoost engine

Our comment: We agree with this too, but we note that Ford and GM marketing diverts attention from the turbo itself to the entire engine. Buyers may never realize that the 1.4-liter engine in a 2011 Cruze Eco, which gets 40 mpg on the highway, has a turbo at all.

Green cars can now be luxurious too

Say "green car" to some of your friends and watch the thought bubble form over their head--with an image of the Toyota Prius hybrid. But in fact, new entries from Mercedes-Benz, BMW, Porsche, and other high-end marques include hybrids, diesels, and unexpectedly high gas mileage.

Examples: 2010 Mercedes-Benz S400 Hybrid, 2010 BMW ActiveHybrid X6, 2011 Porsche Cayenne S Hybrid

Our comment: In a way, this simply returns to the classic auto-industry approach. Traditionally, new and pricey technologies hit the top end of the market first, and then worked their way down the food chain. (Think automatic transmissions, air conditioning, and so forth.)

To make sure we knew that their site was searchable, the good people at AutoTrader also tossed in a list of the hybrid vehicles that were most searched-for. The top five were:

First: Toyota Prius II

Second: Toyota Camry Hybrid

Third: Ford Fusion Hybrid

Fourth: Honda Insight EX

Fifth: Lexus HS 250h

[AutoTrader]