Yeah, I have to agree with everyone else here - gorgeous palette. There are a couple areas for improvement, though - I think the lack of antialiasing on the hair is really noticeable, and the anatomy on the arms is a little awkward (although the pose is plenty dynamic, which I think is usually more important).
Impressive use of colors and dithering. The composition you have going is helping this be more badass as a piece as a whole.
I like what you did here Paul McCartney.
Hey Tatiana, this looks really cool, but could you fix the palette somehow? It has over 500 unique colors!