I was reading over the Nauker thread, and it got me to think about a way by which questing could be overhauled to eliminate some of the more obvious abuses. And it all starts by eliminating quest giver trees/stones/etc and replacing them with a randomly generated set of coordinates and a range around them.
Rather than having a quest giver occupy a tree, have them instead be a nebulous force that asks you to do tasks for it. Whole discussions could be had on how to contact a spirit, but the present method of 'One Just Speaks To You' seems to work just fine.
Once contacted by a spirit you'd be given a task that must be carried out within a certain distance of a randomly generated location. It's important to note that the possible location should never be a static point, but instead be a 'follow the spirit's guidance until you reach said location'. Then you just follow the indicator until it changes from a tree to a sun (or whatever).
This eliminates the ability to road to quest givers (thereby eliminating 'gaming' that aspect of it), while still retaining most of the current aspects of questing.