I think blizz are desperate to get rid of the shitstorm we call pandaria. my guess will be march 2014. They can afford to keep it running until late 2014, but they won't. Here's why;
Every time we get a report that blizz has dropped x amounts of subs, people start to think that "hmm, this game seems boring if that many people quit". Call it a chain reaction of sorts. Of course many people are not subjected to this chain reaction, but many are. The people affected will also see the boring aspects of the game. "Why should I pay to do raidfinder with a bunch of idiots who don't know what stop attacking means" <---- these types of scenarios are what the so called casuals are experiencing right now.
And most of the people quit halfway through raidfinder not being able to gear up to at least enter a decent group for flex (since they all want you to have killed garrosh on normal, link the ahead of the curve or have a shitload of ilvl). What are the casuals paying for now you ask? Some shitty pokemon game, one living steel a day and a bunch of dailies no one gives a crap about.
SoO patch 5.4 was fun. The first two weeks that is. After method "brought down" garrosh, only a few guilds did the same. Two months in, there were only 45 guilds that had "killed" garrosh. As of now, there are only 104 (0.43%) of the guilds that have defeated garrosh. The usual complaint (before SoO, and MoP in general) was that the bosses were boring and/or too easy. SoO was not easy. It was hard, but also boring. And really, really not fitting the image of the direction blizz was going with the simplified talent system and whatever they had in mind. I'm not saying it should have been easier. But the mechanics were so boring and needlessly overcomplicated. You can't really call that hard. Just mind-numbing.
Where am I going with this? This: They want to pull the plug on mists of pandaria as soon as possible. The beta will most likely launch in january. The game is already coming to dreamhack winter (which is in 3 days from now) so the game is almost finished. Otherwise they wouldn't be showcasing it in a major event.
While they are completing the finishing touches before the closed beta, the subs will continue to drop. They can't afford this. Not from a financial aspect, but their reputation is at stake. I mean, who would want to play a game where the players are rushing to quit?
I don't care if SoO were to be the new ICC and last the entire year. But what differs from these two is that ICC was enjoyable. Lich king was a great boss, the best after illidan. I loved every aspect of it (besides the stupid debuffs on lich king). SoO is not enjoyable. The only thing that could have brought joy from SoO, even with lame mechanics and drawn out fights, is if we could kill Garrosh. But nope, he gets captured only to break out and leave for time travels. This sucks.
I am not the only one to enjoy ICC so much that I stayed the entire expansion.
The numbers here show that the subs actually increased towards the end of ICC/beginning of cata, only to drop Q1 2011 directly after the release of cataclysm.
From every aspect, mists of pandaria was a disgrace to the name of WoW. It didn't bring anything to the table. It took away what was good with WoW and left like an ungrateful little brat. And the people at blizz still scratch their heads and wonder what went wrong..... They will attempt to pull the plug on pandaria as soon as possible. Late march 2014 is the release date. April at latest.