You ever get tired of killing the orc that hangs out in the same spot under a tree, or loathe passing by the lost hobbit that needs help, despite the fact that you have watched her get escorted countless times? Maybe, maybe not. But if you are like me and the countless others who are tired of seeing static worlds, then you might be interested in hearing of a solution. This is a next-gen solution though, and is not a catch-all.
Currently, worlds are set to be static, because they are easy to pull off. But with a static world comes a loss of accomplishment. However, to make a world truly dynamic could be disastrous under the current construction of worlds, as they are small and packed with players. This would lead to many people going through content too fast to which others would be left out, not to mention the complexity of it would be difficult to pull off. There is another fix though.
Progressive servers could be the next logical step. To explain, the basic idea is moving from one world to another changed one after so many quests are complete. This would unlock the next set of quests, and going through the world, players would find that the quests they did had an impact, through buildings being different, people no longer being lost, monsters that were supposed to be dead staying dead, and so on.
Some people would see this as being an issue though, especially to socializing with newer players, or the Auction House (present in most MMO's). This is easily fixed though by allowing the player to go back and play with newer players on the old version of the world if they like. As for the AH, that should merely be allowed to span across the versions of the worlds.
Progressive servers would allow for new gameplay options by changing the dynamics of how quests could work with different environments (the old world vs the new). This is by no means a perfect solution, but it is better than the standard worldset we get now with any MMO. This server type would create an evolution in the step to a dynamic, breathing world that we can all enjoy someday.