Thanks Docter for your initial post illustrating examples of why you think GW2 has potential to reshape the MMORPG market -- it was probably the only thing saving this post from getting closed. This discussion, like stated earlier, isn't about GW2 vs other games but rather what GW2 offers in today's gaming market and how it could shape future gaming models.
I believe subscription games are going the way of the dodo - at least for newly releasing games. B2P and F2P offer a smaller gating due to not having such high cost thus opening themselves up to a larger market that wouldn't normally try a game due to reoccuring costs. There are definitely right and wrong ways financially to do these gaming models but for the most part, it is hard to fuck up. I think this will go beyond just MMORPGs as we have already seen with MOBA games, as we hear more and more about RTS and FPS games joining this model.
I am unsure about the removal of the holy trinity model but I do agree that it is a substancial change that could be a real difference maker in games - we will have to see how it will work out for GW2. I know there are definitely some people who will miss it; however, if the game ofers an interesting role system to combat this, it will make the change much less drastic on those players.
I definitely see reactive combat picking up quite a bit in MMORPGs as we hear praise across the board for games like TERA's combat system. I actually don't have much to add on this :/
I would like to add a few things to the list: the downleveling system (mentor system in Rift) and the removal of mob tapping. The ability to play with friends no matter what level they are will be a dealbreaker as future games start to come out. A couple of the complaints we constantly hear are the missing social aspect of games and the large amount of time it could take for one to catch up to their friends to play this cool content they are playing - with both of these changes, it promotes grouping aspects as well as removing part of the stigma with having to catch up to your friends.
Going to end it there sadly, wife wants to play Diablo. There are quite a few systems that I feel are important to the future of gaming that are evident in GW2 - can't wait to see them.