The hair looks very flat, with no depth of the numerous strands. It just kind of looks like blocks of color with some surface brushwork to give an illusion of strands...
This is one of the better tutorials to explain how to paint hair:
http://features.cgsociety.org/story_custom.php?story_id=3174

Thank you very much for the tip about painting a realistic hair. Anyway the idea about this fashion wig is to offer something like those colored wigs used in dancing parties just to have fun. Only pop stars could use this kind of wig to go shopping.

Ah, those who are so cynical. I think it's great. You made an effort, it looks good, and no one can say that their's is better. The roots at the head are a nice touch as well.

Interesting work author...GL