One of Guild War 2′s consistently mentioned selling points is that it strives to turn the concept of a typical MMO on it’s head. The main change in Guild Wars 2 is the move towards a more balanced class system, rather than the “trinity” of tanking, healing, and DPS.
We already knew that this was in the cards for GW2, but only recently was it revealed that this was partially inspired by Team Fortress 2‘s class based system. Designers Ben Miller and Jon Peters stated that they wanted parties to have a more organic feel to them, like everyone could contribute in a meaningful way, without having to fulfill prescribed roles.
In regards to that elephant in the room, Peters had this to say: “I just detest dependency and the lack of teamwork it creates. It seems awfully silly to get people to play together and then not have them interact other than to say ‘are you doing your job?”