Looking at the new red at the car show, it sort of looked like a lipstick red with a pinkish hue and was solid plastic color. The old metalic red is painted on (vs. mixed in with the plastic) and has an orange hue. I like red, but I don't like either Smart version but that's just me. From a distance and not comparing it to another red, you probably wouldn't notice any difference between the two.
As for the picture, it could just be the camera's CCD interperting those two reds as the same. Something I notice in Sony cameras, especiall the low end like the S650. I did a simple photoshop color correction and desaturated the color (low end cameras tend to have color cast issues as well as oversaturate colors). Now you can see that the car on the left is more orange than the one on the right.