This game is not WoW.. This game is not EQ.. This game is not Diablo 2
Do not come into it expecting it to be a mirror of any game played before, it has new aspects that I find absolutely breath taking. The graphics are stunning, the gameplay is awsome, and you'll find yourself picking skilled players over high leveled players for missions, because I've seen some really stupid level 20's cause wipes in groups, while level 15's with a brain help pull us through. This game relys on skills more than items, more than levels. So bring you're best gaming gloves, and hop on the guild wars band wagon.
This isn't the "usual MMORPG". In fact, it's not an MMORPG at all. There is nothing Massively Multiplayer about it.
Having said that, it does have the feel of an MMORPG because in an MMORPG you primarily interact with groups of 4-8 people while grouping. It's the same in Guild Wars, and there are the same kind of interlocking dependancies between classes in group composition.
One of the main draws of the game is that PvP is structured, rathre than essentially a free for all.