Anatomy looks nice, but i strongly dislike the colors, not quite sure why. I'd lower the saturation on the skin and shoes.
Shading is completely random, trunks are shaded one way and then the lighsource changes, as seen on the shirt. And neither limb or head are shaded. Add more careful and consistent shading, and it will benefit.
Those red letters on the blue background are burning right through my retina into my brain. Don't do it again, it hurts. And use the [img] tags fer cryin out loud. Don't link to imageshack pics that have ".php?" in them, link to the correct one (use the Preview post button, right next to the Post one, to see which link works best).