Isn't this the same guy that posted back during Cata that the next expansion was going to be about the revenge of the legion, going back to Outland, exploring FOUR new worlds including Argus, and getting two new races, Etherials for the Alliance and Coralfin Naga for the Horde? And then instead we got Mists of Pandaria. (which I have loved.)
I will buy into two things here:
The Dark Below
Both of those make sense to me. I think the rest is just really well thought out speculation.