looks very sharp, nice and clean! good designs and textures! pretty awesome i think!
my only crit is the relationship of the building behind the water thingy (forgot their actual name) and the sun, you may want to consider darkening the buildings behind it just to give it abit more depth. (my opinion)
apart from that, its looking crisp!
this a still image or you going to stick a character on it? prehaps it can do abit of half life action