not in my opinion. I see the different colors coming all the time and would say that black, winter gray, and blue ribbon would be the hardest to maintain. White, silver, and sandy beach would be the easiest to care for.
A pearlized white is actully much less prone to show dirt than a pure white. I wouldn't have sprung for the white paint if it wasn't pearlized. Truthfully, it shows much less dirt than previous white cars I have owned.
I agree with Tideland. In Hawaii silver sells better than any other color for that reason. Easy to care for and doesn't show much dirt. The white tends to show dirt slightly more than the silver and is the second best selling color in every model we sell. We don't sell many black vehicles because of the tropical heat.
White cars are the most popular in Australia. I am not going to guess why, they just are. It seems odd but white is easy to keep looking clean.
My prior car was a Blue Silver which hid the dirt very well. So far my Blizzard Pearl seems to hide the summer type of dirt well. Had it for about 10 days and have already had to drive it in a few rains. The bugs show a bit more and the dirt in the door sills is quite a bit more noticeable than I'm use to (but hey the car is white). I'm may be a little OCD when it comes to wheels. I have a V and I think it may be a little more challenging to keep the wheels around the lug nuts clean. A soft sponge seems to work well but the winter build up may be a pain in the butt. Only time will tell.
Basic dust doesn't show - road dust (black) does start to become obvious on the rear after a bit. Bug splats on the bumper are super obvious in high quantities. All in all, still by FAR my favorite of the available colors. Now if Matador Red or some other pearl-like Lexus non-white came to the Prius, I may give a second look (yea, I'd pay the $220 premium on those too).