i'm really digging the character design and the perspective. it ends up looking kind of fish-eyed, and i don't know if that was your intention, but it looks nice. then again, it might just be his pose with that perspective making a fish-eye illusion.
but i think the one thing you could do to improve this would be to soften up the edges. the figure itself looks very cool, but the whole realistic illusion gets a bit cut short because he doesn't relate at all to the solid white background until you see his cast shadow. maybe if you just lightened and softened up the edges of the whole silhouette it would really start to look great.