"A part of the achievement system rollout is a new notification system, which we will be taking advantage of later in the year to create a smoother tutorial and introduction for the game."
Very nice, that plus the achievement system are things that will serve AoC very well.
But it's too bad it comes so late.
As for T6, well, nerf T5 a bit before, overall the gear from there does not justify that tier being harder than T4 at all (and why on earth DT and barb get so much more love from there than every other class ?).