5) New Raid Dungeons
Blizzard's approach to top-end content such as raiding is getting casual. There will be three raid dungeons in the game at launch, and you'll only be able to hit each one once a week. Your guild won't expect you to do 10- and 25-man versions of each – because you won't be allowed. If you're a more casual raider, expect to spend a night or two a week working on available bosses. The hardcore can create an alt and have a second go, or hit the tougher 'heroic' modes.
4) It's A Freebie Apocalpyse
Even if you're a casual WoW fan, or a tourist, it's worth creating a trial account just to see the destruction wrought by Deathwing's ascent. Trial accounts will be able to access all of the old world, and see the changes in completion: all of the craters left by Deathwing, all of the new quests, all of the new stat changes, even the dungeons. The only price is the (gulp) vast download – although a better implementation of streaming means that you'll download chunks at a time while you play.
3) Easier-To-Understand Stats
The maths of WoW is hard work and doesn't make much sense. Why should you care about arcane concepts like armour penetration and mana-per-five? Blizzard's answer: you shouldn't. Now, even the most numerically illiterate players should have a better understanding of their class thanks to a complete statistical revamp, and a rethink of how information is displayed in the interface and ability descriptions. Yes, at the top end, you'll still have theory-crafters telling you your gems suck. But at least you'll understand why.
2) A Daily Event
Wintergrasp, the open PvP zone that was introduced in Wrath of the Lich King was a fun failure: unbalanced, and riddled with lag problems. But it's getting a sequel, which should address many of the issues. Tol Barad features constant skirmishes between Horde and Alliance over an island prison – you'll need to capture and hold control points to defeat your enemies. Winners will be granted access to a small, lunchtime scale raid dungeon. But win or lose, Tol Barad will act as a focus for daily quests and reputation grinds.
1) HE'S A BLOODY MASSIVE DRAGON
You won't be able to kill Deathwing when Cataclysm launches. Oh no. Like Arthas before him, he's been saved for the final boss encounter of the game. But his model has been leaked, and spotted in world events already. And he's enormous: ten storeys of lava-breathing, iron-plated, spot-welded gristle that's clearly going to bake a raid in seconds. Raiders: learn your lesson early. Stay out of the fire.