I'm not really a fan of it so far. It's just a very generic grind quest followed by another grind quest and another and another. Playing catch-up, particularly on the sigil and valour grind parts, is nothing but a chore.
I'd like for the actual *quest* to be interesting. The Warlock green fire chain in 5.2 has been a thousand times more fun and engaging than any of the Wrathion quest line in MoP up until now. More challenges and less grind, please.