Here\'s another of my 2 cents. (I\'m starting to go into dept

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I think that quest based character advancement would be nice if implemented properly. Certain skills can always be trained, but the training could be easier (or you get a bonus) for skills related to the quests. I.E. a quest that requires that you sneak past a monster (which you have no chance of actually killing) gives an \"additional\" bonus to your hiding/sneaking/whatever skill. The beauty is that you are concentrating on an activity/story line and the advancement is a secondary reward.
Quests that end an item reward, involve killing a monster for an item, or involve retrieving ANYTHING of rarity should be avoided at all costs. All these quests lead to is camping and auctioning of in-game quest related items, which effectively disolve the system in place.
Another possibilty (which may be hard to implement on the rules/admin/setting side) is a character history based quest system. The system keeps track of all the quests you\'ve attempted and which you are successful at,etc. When you are approaching a guild/person/etc for a new quest, your quest \'reputation\' defines the things you are known for being good at. This doesn\'t mean you can\'t get other types, but you may be able to get the more complex (and rewarding) versions of ones you trend towards. This could also be a tool to advance personal plots or allow the more dedicated players (and groups) of a specific type to advance the \'world\' storyline. An example of this (to go along with the previous example)would be a thief/assassin oriented guild, whose members have completed a series of story oriented quests. The guild\'s history triggers the system to give them a guild based quest (which can be broken into a series of smaller quests so the guild can destribute tasks to its members) to assassinate an order of bad guys (or whatever). If the quest is successfull, then the \'world\' story is advanced and no more of that specific \'bad guy\' gets spawned....a new threat emerges and the story path is defined.