Its the Sha of Pride, theres Lore in 5.2 thats ays the Mogu were designed to fight against the Old God that 'died' and became the 7 sha, and in success they were doomed because all the mogu were plagued with the negative emotions that they had released, including all the 6 known sha (anger, violence, despair, ect) and PRIDE.
Its rediculous to presume there is a sha of chaos just because the word Chaos was used in a sentence to describe... oh I don't know, a moment of chaotic events maybe? Just because they used the word chaos in a paragraph does not mean chaos is the 7th sha. Now saying they succumbed to all 6 negative emotions that were released AND pride, now thats much more concrete than chaos.
---------- Post added 2013-03-26 at 03:01 AM ----------
Just listened to this, interesting sound file. I can't wait for 5.3 to see if it points more towards The Sha of Pride or the Sha of Chaos. "The sha of pride is the most insidious of all." That almost totally proves it, let's see if it makes it to 5.3 or even is real first though. Even though I may be wrong here on my findings, atleast we figured out what the 7th Sha is most likely going to be. = D