I wonder how many people completed Loremaster of Pandaria. I personally didn't, but I'm planning to do every single quest on Pandaria before WoD comes out
Also when WoD launches, I think the first thing I'll do in the game is Loremaster of Draenor because storyline looks way more interesting than in MoP. For the first time since WotLK, new expansion feels like good ol' WARCRAFT game so it would be a pity to skip some of the new lore.