Blue!
I like the fact that it has a theme, and feel that is consistant. Makes it more movie-like, witch seems to be what you where going for.
Found it kind of odd that the robots looked more like sceletal placeholders from 3Dstudio max. I know how much space 3D content takes up (I use a tone of it in my animations) but I dont think it would hurt to give the robots some detail. It looks as if you are an animator more than a modeler though, in witch case, the box based robots are compleatly understandible.
Good luck with the final movie/seres thing :)