Bumped into a nice map of the virtual world landscape. Based on criteria of Business, Entertainment, Social and Game, Fred Cavazza made an inventarisation of the virtual worlds. I like it because it sort of nicely categorizes the different worlds out there, at least based on their most important features. Ofcourse one can argue that for example WoW is also a strong social environment, so its just a good overview. Additions are welcome ofcourse!