Wow, a lot of mixed emotions on this thread!
I for one am giddy with excitement over all the new content! I'm somewhat inexperienced in the MMO world, this being the only one, but from what I hear we're pretty spoiled when it comes to updates and dev interaction!
For all those who are chaffing over "shared power sets" and the like, if you don't like it, don't use them! It's that simple!
I have a feeling the 35+ content will probably be coming with CoV considering The Hollows addressed 6-20 in I2, Striga for 20-29 in I3, I4 was used to try and scratch the PVP itch everyone had (and subsequently complained about), and now I5 brings Croatoa 25-35.
Of course you just can't please everyone. If the devs were to write a whole new game with all new content you'd still have people who would find something to complain about. Oh wait....