Ha, have to give that one a go. Been meaning to try it for some time now, waiting for a project where it would become useful.
Were I to analyze it, I think the most clear problem is lighting - seems different for the object and background, too many dark spots with that bright background, not enough indirectional light. The normal mapping is good and not symmetrical. You can almost see in the detail picture that the bumps would actually effect the silhouette, and then that would take relief mapping or some such, but is not so clear that it couldn't be made with normal maps. Also, in the detail pic, could be artifacts, but looks like as moisture condensation or very small dirt specles/bumps are added on top of the texture, visible with the rimlight. The model appears very meshsmoothed, expect the scuplts of the throat region. Another giveaway is the blending of the scaled and not-scaled regions - scales fade in from nothing, like when texture painting with a wet brush.
Edit: If you zoom in to chin, the scales seem to bump the silhouette. So not a low-res model with normal mapping, that takes high-res sculpt or using newer shaders, with tessalation displacement.