I downloaded WoW, played it for all of twenty minutes, and uninstalled it. I spent more time with D&D Online; I think it had a better opening.
WoW was like: "Go kill twenty dogs and come back to me". DDO was like "Meet the priestess at the door and help her clear out the dungeon." In other words, you were made to be part of an adventuring party right off. The graphics were better in DDO, in my opinion. There is a scene where you can leap off the edge of a path and drop twenty stories; it's rather breathtaking (and make sure you have the "Feather Fall" cloak, or the spell).
But if there is to be a Pathfinder MMO, then I recommend starting light; consider "Adventure Quest Worlds" as a guide. It's not state of the art graphics by any means, and it's still "Go kill twenty critters". But it loads up quickly and players can jump right in almost immediately.
The other paradigm they might follow is Neverwinter Nights by Bioware. It had a so-so adventure to play through, but the game was revealed as a real treasure with its multiplayer aspect. Hundreds of worlds created by fans, some with complex storylines and role playing experience, some as simple as "Team A and Team B try to kill each other's king/dragon."
In fact, if I were going to make an MMO, I would make it almost exclusively the latter: Two or more teams going at each other tooth and nail, over and over again. $5 a year. I'd be a millionaire in six months.
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