" Perhaps with study and patience, the Emerald Dream may become open eventually... but for the time being it remains closed to all."
This is kinda cryptic, but what I can interpret is that it is a World Event where someone with a lot of patience and study needs to figure out or farm a rare random item and figure out what to do with such item. Once the Emerald Dream is triggered, everyone else might be able to enter the Emerald Dream permanently.
I wrote a compilation of quests that seem to tie in with the Emerald Dream. Hopefully someone is able to figure out how to open the Emerald Dream. There is a quest with Hammul with the Wailing Caverns and another with Umbranse that stopped abruptly with no follow up. My guess is that Umbranse is the key to open the Emerald Dream. He lost an Augur Device that we need to find.
http://www.blizzplanet.com/modules.php?act=News&id=147http://www.blizzplanet.com