Above are some pieces of concept art produced for Diablo 3, as a fan of the series it is hard for me to be too critical, but I will give it a go nonetheless.
To begin with I would like to give praise for the consistency of style even between artists, and also the fluid, suggestive nature of the brushstrokes. I am always surprised when I see concept art that is immaculately polished, to me that does not make any sense in production. The amount of time spent going in and rendering every single detail could be much better spent producing several concepts which suggest detail in places. Also when it comes to environment painting, I believe lighting and atmosphere are so much more key than painting in every nut and bolt. I feel the artwork presented here embodies that attitude and also gives it a sense of purpose.
On a more critical note I would say some of the pieces released are perhaps a little drab and lacking in vitality, and while the conveying of ideas is very strong, I think more exploration and experimentation would have "freshen" things up a little, however the release of this material is a marketing affair so maybe only pieces that conformed to the style were published.