Geldon Yetichsky, of the blog Digitally Staving off Boredom, wrote an interesting piece about why he canceled his City of Heroes account. He contends that CoH is lacking one important thing: Nothing really changes. Aside from a few pieces of dynamic content like Recluse's Victory, Safeguard Missions, and the Rikti invasions, nothing ever permanently changes the game world.
CoH is (almost 4 years later) still one of my favorite games, and the MMO that brought me around to actually liking the genre. As much as I hate to admit it... he has a point. No matter how many times you lay the smack down on the bad guys, or rescue a damsel in distress... none of it has a lasting impact. The bad guys continually respawn and the same seemingly hapless citizens always need to be rescued.
What he wants to see is a game world so full of life that it actually disrupts and inconveniences players. A game world that is more like real life, where actions have real consequences and where change is an everyday occurrence. As Geldon says: change and consequence may be inconvenient, but without, there can be no real meaning of player's actions in a virtual world. I couldn't agree more. He offers EVE Online and 10Six as exceptions, but there is another.
Tabula Rasa has ongoing, contested battlefield control points, and the Bane unceasingly fight to take control of them. These dynamic, world-altering areas are at times completely inaccessible. They're important because they not only house teleporters, hospitals, supply depots, but also mission NPCs. Additionally, you can earn tokens for defending and taking back these CPs. Participating in these skirmishes really gets the blood pumping and what you do has a direct impact on the game world. All in all... it's something we need to see more of within the genre.