Perhaps a way of think of games in terms of a larger set of interactive art is as artificial worlds. Like a biome in the Eden Project, each has artificial rules superimposed upon reality in an attempt to craft a place. Each is different, bounded by the systems that give them form, but full of possibility and indviduated experience.
You could call them ludomes, ludic (as in interactive play) biomes. Perhaps that makes us all ludomancers, which makes the URL of Daniel Benmergui's blog oddly apt, no?