I'm going to put down Wrath because of the storyline that was playing out and the resolution of a major part of Warcraft III's story, and its huge advancements beyond TBC and Vanilla. Cataclysm continued those advancements but they were incremental beyond what Wrath delivered, and while it was great at the start I feel like they missed an opportunity to explore the character of Deathwing and make DS more satisfying (it wasn't awful like a lot of people say, some good fights some bad, just wasn't amazing like an end of xpac raid kind of should be... it was just another raid. Spine of Deathwing was great though).
MoP has shown a huge step forward from Cata, adding so much new content I damn near killed myself trying to do half of it. And a lot of the little touches here and there have been awesome. Maybe by the end I'll actually say it's MoP.
---------- Post added 2013-03-25 at 02:12 AM ----------