If you recall, they mentioned at BlizzCon about possibly having Chen Stormstout show up at the capitals around Azeroth. Seeing the lore rollout plans with Lili's Journal, Pearl of Pandaria and it's follow up, I cannot help but wonder if Blizz was originally thinking of having LiLi show up at the capitals looking for Chen and through quests and such, you would join her in looking for him. Much like the elemental invasion for Cata, would have spanned the month leading up, introduced the characters for the next expansion and given us lore geeks and bored players a break from DS raids.
I also believe Theramore was also intended to be part of the prelaunch plans, but as an introduction to the scenario system, not the expansion entire. Theramore could be done separately to continue to drive the story forward into MoP.
Take the two, combine them, stretch them out over from two weeks to a month and I think there's something there. Why plans changed or if they changed, I have no idea. But it's a darn shame.