Im stunned no one has pointed out this sentenced from WoWWiki about Azeroth.
"The world of Azeroth also has lands located at the other side, beyond the Veiled Sea to the west of Kalimdor, and beyond the Forbidding Sea to the east of the Eastern Kingdoms. No one is sure or has knowledge of what kind of creatures, lands, cultures, life, and sentient being lives in the other side of Azeroth. It is clear though that it is very dangerous."
This can be found on wowwiki.com and serch for Azeroth (world). I would link this but since im new I can´t link to other sites yet.
I´d guess is some point we´ll see this new land.
I don´t think emerald dream will be a full expasion pack. since, what is there to do there. There arn´t many people there(for questgivers) or cities(For people to hang in), creature for you to farm.