That's pretty cool. Might speed up asset creation for games by orders of magnitude: Train with concept art, generate the variations via these networks; adds consistency to the output and helps loosen the asset bottleneck / content treadmill esp for smaller studios/individuals.
Not directly related, but here are some results from a similar algorithm[1] combining the Starcraft map Python with various Google Maps screenshots: http://i.imgur.com/EgFpqRA.jpg
[1] CNNMRF, Neural Style plus Markov Random Fields: https://github.com/chuanli11/CNNMRF