[Androsynth]

In MMORPG's the rewards are a big motivating factor for playing, but they're not the only factor.

WoW still has very well designed game mechanics that are fun on their own. Learning (ie advancing up the learning curve) and decision making play a big role in having fun in RPG's. These are also true game mechanics (meaning they're fun without reward mechanisms).

On one end of the spectrum would be a game like Team Fortress 2, which is fun because of it's mechanics; on the other end of the spectrum is a Zynga game that is fun for the reward mechanisms. WoW, and other RPG's would be somewhere in the middle.

[sbov]

There's even a range within RPGs itself. E.g. I would say that Diablo is about at the same spot in that scale as Zynga games are.