Good, but could use some work
I would suggest to down the specularity of the green/blueish stuff. It makes it look like amateur 3D XD. If you are going for the spotlight effect that this picture has, the rest should be darker IMO. Try to give a smaller value to the other lights. Also, don't let the other lights effect the specularity. There are some strange dents at the side of his mouth. This is probably because of a bad topology. You would need to remodel the head to get rid of it.
Now for the good stuff :D The metal texture is very likeable. I like the Tangent effect it has. The robot also seems to be truly happy. The pose ads to his happiness. Oh, and one point for it being Gir :D