The diffuse textures are in fact the Sunburn textures that ship with the default project. Normal/Specular/Displacement maps are generated with Crazybump. Crazybump did all the generation work, and with Sunburn it was simply drag&drop in order to get the current results. A lot of material tweaking can be done with the Sunburn Editor. I might show more about that later, as its only a small test for now.
Note: The floor is very stretched. It probably makes the cubes look better by comparison ;)