I've played the 7 day trial and you're right, its not a typical MMORPG. Its more of a fixed size game world that you can play with others. It has a few areas that are more akin to the random encounters of a MMORPG, but for the most part its pretty limited in size (and apparently replayability).
I enjoyed it, but I can see how it would get old once you've done all the various quests.