I played SW Galaxies, WOW and GW for a resume.
I liked the massiveness and configurability of SWG. I hated the time suck later but when I started to play, it was great.
WOW - wasnt my thing really. Played to try and meet up with my brother but he was lvl 60 and I was just starting.
GW - thought it would be different. Great tool to use if you have a group and want to game together but falls short as a game all by itself.

Major limitations: fully interactive environments. Cant shoot down the trees.
😀 Advantages: lots of competition available. Play isnt limited to just your PCs horsepower.
:idea: Its the advantages that I want to talk about. Think of AI and the challenge PC games have generating it for multiple enemies on just your PC. Now imagine a grid of PCs all linked together singley responsible for only one AI each.
We are getting the computer power to do this. Deep Blue played chess and beat the best. I dont need that level of computer skill, I just need a challenge.
What I see is a world that is controlled by 100 or even 1000 seperate computers all located at a hub. Each computer controlles a Boss and his minions. Each computer reports to a world computer that is responsible for maintaining the environment. One computer plays the roll of the God computer who can change the rules that the Bosses play by and the rules that the world follows. Each Boss has his/her own motivators and things that they try to do. Although their play is in real time, their thinking and processing is at full multicore speed.
Results:
The world is constantly changing. - but slowly. Like the SWG model of creating buildings. Items are constantly in creation as well. By players and bosses.
The world can grow as well. Foliage changes with the seasons. Wildlife works on AI and will avoid city growth until cornered and then will retaliate.
Players interact with minions and when high enough can interact with the computer Boss - who is unpredicatable.
Computer Bosses wage war against one another and grow cities, raze cities as they see fit.
It would be like a world full of Deep Blue PCs, all playing Command and Conquor while you are in the middle playing Crisis.