Back in 2005 I got to speak with one of the guys formerly from Cyan Worlds regarding MMO's after their whole Myst/Uru thing went pear shaped. He was working on Guild Wars (1) at the time and said their main focus was letting the players participate in a story - the gameplay was all geared around enjoying the setting, with a central element of "fun combat", not in terms of maximizing subscription time.
I never had time to play GW1, but I suppose when your profit model is not based on months subscribed but only game discs sold it drastically changes the resulting product. It remains to see what happens when this hits the street. The amount of effort put into gameworld verisimilitude is impressive.