Having never played, and having no interest in playing a druid, I can say they'd have to do quite a lot through the lore to interest me in an Emerald Dream/Nightmare-based expansion.

It sounds like an interesting concept, but I've never heard anyone who wasn't a druid (or night elf) express interest. It just seems like it'd be far too focused on the lore of one class to make it approachable for everyone.

I would also love to have some more lore in-game to do with the emerald dream, though unfortunatly the emerald nightmare (which I was really looking forward to as an in-game thing, imagine the crazy stuff you could do in a realm with no rules and nightmare-like crap going on) seems to have been mostly dealt with in the Stormrage novel :(

The problem with that is that they fixed that already and they had a whole book on it...
If you want lore on the emerald dream read the book "STORMRAGE" by Richard R Knakk

@BgRdDragon: Please don't encourage people to read anything by Knaak. He's WoW's Ed Greenwood.

Well they didn't completely fix the emerald dream, and there's a music file in Cataclysm named after the area that is still affected, so who knows.

Stormrage was actually a pretty decent book, far better than Arthas was the year before.

You must go into the Emerald Dream to search for the darkness plagueing the realm. Upon entering, you are teleported to the town of Tristam. Clearly... the scourge has taken over the land here... a priest tells you about a demon from the Outlands that's underneath the church terrorizing the remaining locals. You realize that you're character's level is all the way back to 1. You begin to QQ but then you realize your playing the Diablo MMORG...

What about the next expansion being all about the fourth war. Alliance vs Horde. We'll get a new heroic class of some sort, as BLizz has pretty much said, and the Raids could be unique in that they are against various faction members. Kinda like TotGC-ish. As Garrosh and Wyrnn's racism reaches new levels, Thrall and Jain will start up a neutral alignment. Now players can choose which of three sides they will play or... I dunno, these are horrible ideas. I do like the "4th war" kinda deal, seeing as that feels to be the direction this is all going.

The emerald dream affects the current plane of azeroth as well. It was even mentioned that ysera has been corrupted by the old gods and that the nightmare seeks to jump out of the emerald dream to control azeroth. They could make a full expansion with the lore and have a war on the nightmare beings.

Yeah..... if only.