Nate Combs at Terra Nova has written a really interesting post about economic and other relationships in Eve Online. It's at at My friend's keeper, and it reinforces my suspicion that while World of Warcraft is the bigger social phenom, with the largest bleed-over into art and ordinary life, Eve Online is the most interesting major game, both legally and structurally.
I'm not even going to try to quote from this one — if you're interested in Virtual Worlds (or political economy or political sociology) you should just go read it.
Update (12/8/07): And see the follow-up.