Launch is one of the most special times for an mmo, because everything is fresh and new. It's really fun to wait for the servers open up (obviously there are going to be queues), then log in and see all the people jumping around, killing first mobs and talking in the chats. Also leveling your first character along with the majority of people, so that the entire leveling experience is epic, with lots of people, meeting new friends and world pvp. With this staggered launch strategy, there won't be such thing. So many people are high level by now, I'm really afraid this "fresh and new" feeling will be missing.