I promised you notifcation, and as your spy across the pond that's exactly what I'm doing. I can report that the Mists of Pandaria launch went off just as described, until a certain point which surprised me.
As I stood in Stormwind, a quest popped onto my screen, with an accompanying message in chat. "Mists of Pandaria has launched! Visit Stormwind to begin your adventure." The quest, The King's Command, sent me to Stormwind keep immediately for a briefing with King Varian Wrynn.
I proceeded as instructed, worried that I would encountered Varian, coated with so many players that I could not possibly pick up the quest, or hand in my automatically collected one. I was pleasantly surprised that, as I walked into the Keep, I was immediately taken into a cut scene. My screenshots of said cutscene unfortunately don't appear to have worked, but trust me, there's a cut scene. I'm not going to spoil it for you, but after the cut scene, I was teleported outside the keep, where this happened.
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