How can I tell that the Prius next to me on the highway is a 2010? My wife thinks the only way to tell is by looking at the Toyota emblem on the back, if it is blue inside the silver then it's a 2010... could this be true? Also, who started the rumor that Prius owners wave to each other? I keep waving and no one is waving back
Look at the side of the cars. There is a much more prominent crease a few inches below the windows on the 2010.
I know that lots of modern cars look alike, not like when I was young, but if you can't tell the 2010 from the earlier models you are in a world of hurt. Just think of the melted down one with soft lines as the older model and the crisp, sharp lined one as the latest iteration. They look alike just like all 5 door vehicles do, but not all that much alike. You should be able to tell them apart long before you can see any insignia. That longitudinal crease below the window line is a dead give-away.
The antenna is shorter and fatter on the 2010, though both do have ridges ;-). The door handles on the G3 kind of have an indentation in the door for them which isn't present on the G2. The rear tail lights curve upwards at the top and are LED. There's the quite obvious front of the car distinction as well. If you are REALLY good, you can notice the slightly higher back end and less slope due to the 3.5" further back top of the car. Maybe that will help give you some things to look at next time.
The front end is entirely different. Gen 2 has those skinny headlights that rides up over the front fender. Not attractive to me and other cars that do that (Maxima, Altima, G35) are not my cup of tea either.
The 2010 spoiler is black. If the 2010 has fog lights it's a V. If there are rectangular bumps under the headlights & circles on the front bumper corners it's an AT.
From the front the easiest way to pick the 2010 Prius is the headlight profile. The 2010 model has the jagged-edge, lightning bolt shape. Very distinctive and quite unlike other Toyotas. From the back, the blue infill in the logo and the flat black spoiler.
All really great ways of telling- also, the purse or wallet of the driver is much thinner. (Oh, and mine has a big black roof on it with a grey grid thingee.)
The gas door thingy - it's a circle on the 2010, square on Gen 2. I was leaving a grocery store parking lot two nights ago at the same time as someone in my car's twin - Gen 3 in Blue Ribbon. I made sure to be in the lane next to him when we got out on the road, and we waved! It was my first wave, and it had me grinning the whole way home
The generation III has a pig nose. http://www.infowavemedia.com/wp-content/uploads/2009/07/Toyota-Prius-2010-Front-View.jpg
The spoiler on the 2010 is always black. It is the color of the car in other years. All 2010's have a place for fog lights.