Interesting concept. Have a virtual world that is continually 'under attack' and then reward users for defending it, as well as their participation in the world. Part game, part user-created freedom... I guess this might maintain a level of excitement/sport, that brings people together, as well as having a serious, creative side to it. The problem with many open virtual worlds, is they can feel a bit 'up in the air' and directionless. This idea might stimulate people to keep involved. Like it.

I'll do a post at Ade's Press soon enough, where I cover games as well as independent crypto stuff.