The answer, dear Exogenesis, is that the switch from Wrath to Cataclysm is going to be fairly real time, as far as we know right now. Let me stress that is the current state of our knowledge. There haven't been details officially released, as far as I know. There's some good argument that would indicate there is a time passage, since time passes faster in game than in the real world. For all we know, it could be a decade passing during the eventual in-game event that releases Cataclysm.
As to how the trees got there? Magic. Here's the basic rundown of what's going to happen with Cataclysm, as I understand it.
There's this big angry dragon who basically hates the whole world. This dragon, named Deathwing, is going to fly over the continent and wreck it like a bull in a china shop. Fire, lava, destruction, all that kind of thing. The rampant magical energies used by Deathwing will radically alter the geography, causing water to rush into new places, the earth to crack, and all of Azeroth to change.
The druids are going to take this opportunity to get their hippy on, and use magic to plant trees and make them grow where they could not previously. There will be more details in quests, of course, but that's the basic idea of what's up.
"With each expansion, accumulating gold got easier. Filling up my bags with gold while grinding and doing dailies is much faster now than it was in BC. BC was also easier than during the vanilla days. Will Cataclysm do the same? Are we up for another inflation round?"
It's a little tough to say. Server economies shift according to each raid tier, with relatively little dependence on the overall expansion. That being said, I think you'll see Cataclysm being roughly equivalent to where we've been -- gold wise -- ever since Sunwell. See, I actually don't think it's easier to get gold (relative to level) in Wrath than it was in the end of The Burning Crusade. The Sunwell dailies might as well have been a giant ATM, and all of us had infinite checking accounts. I actually miss those days.
"When did you first realize WoW was amazing?"
I'm going to get a reputation of a useless sap. The others will never let me do The Queue again, and I certainly won't get flirted at when I get to BlizzCon. But that being said: I've always played one game or another, usually because my friends were into it. But, this time around, I really got into WoW the first time my wife got to do an instance. She was very excited and kissed me because I tanked for her. It's been her first video game, and has been something I could share with her. That made WoW unbelievably amazing to me.
"My question: When are female warlocks getting incubuses? I want my demonic belf boy in hotpants!"
This kind of sexual parity question comes up a lot, though I'm more accustomed to seeing the question as "When do female warlocks get a female Metamorphosis?" Sadly, the answer still is: I don't know when, if ever. A secret, dark part of my soul is hoping to see a female metamorphosis added for Cataclysm, but I wouldn't bet on the incubus. Building models for the game takes up time and resources, and some things just don't seem to be on the priority list.
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