A quick comment about really dark skin textures. All skin has a natural sheen which comes out as highlights on photographs (even in the most controled set-up). This highlight is not seen so much in the lighter skin textures because it blends in, however the darker the skin tone is, the more glaring this highlight appears. As such it is very hard to get good resource photos for dark dark skins. I recently made a mid-range black texture for apollo maximus, and it took a long time to get the highlights that were there to look proper. (see brutus ultimus at www.rawart3d.com).