Before I had my own flock, I got eggs from a neighbor and there were generally 1 or 2 blue eggs in the mix. I'd never heard of blue chicken eggs before, but I noticed that the yolks were bigger and much brighter orange than the brown eggs I got from the same neighbor. They also had a much more substantial "yolky" flavor. When we started planning our flock, I read all kinds of stuff about different breeds, and the question came up again and again about whether blue eggs tasted better or were in some way nutritionally superior. One thing I did read about the Ameracuana breed is that they are excellent foragers and that the differences people notice in the quality of the yolks may be due to eating more worm and bugs -- so a diet with more protein.
I can't speak to whether our blue eggs are different than brown -- none of our brown layers have started yet -- and I'm not sure whether our Blanche is an Ameracauna or an EE -- but she is an excellent forager, and is the most wide-ranging and adventurous of our flock. We'll have to see about the rest.