I wasn't so much skeptical, but I understand the "Developers can invest time to do X, Y or Z" argument. Honestly speaking though, and after trying the beta, it is worth it. even for that 20 mins before raid where you can go into your own little world and design something that is completely "YOU"; so to speak.
from a feature perspective, i can see this eating up a lot of my spare time, and that is really a good thing. plus, and as others have pointed out, it will get those level 60's to go back and do content for the dimension drops from bosses, which in my opinion, is far more viable than doing it for cool looking gear.
It has been my reading that Rift as a game has been heavily criticized for its lack of RP features (hence the weddings and player/guild housing - which players have been very grateful for) as well as PvP content. I feel that this may be a proper long term solution to at least the RP aspect. waiting to see what they announce on the PvP front.
from a PVE perspective, well... 11 patches in vanilla Rift really speak volumes, and I anticipate that this trend will continue well into the future.