nope, i'm a dirty liar.
direct from the M&M's website:
<< Do the different "M&M's"® colors taste different?
The color from the candy shells has no taste. It's the delicious milk chocolate (and inclusions like peanuts and crisped rice) inside, with the crisp sugar shells outside, that provide all the taste and texture of "M&M's"® Chocolate Candies. While there is no difference in taste due to the different colors, consumers do eat their "M&M's"® in a variety of different ways, i.e., sorting the colors out separately and eating one color at a time, allowing the color to dissolve from the candy shell in their mouths prior to chewing the candy, and of course just enjoying them one by one. >>