FWIW, part of what I am trying to do with this gallery is show the power of images to illustrate /concepts/ (or ideas, or systems, or models, ...), rather than just /data/. There is a lot of overlap between "concept viz" and "data viz", in both topics and methods of presentation. But I still think there is a difference worth pointing out, especially since "concept viz" is a lot trickier and less developed.
(Great. It seems I've turned into a recommendation bot :)