The World of Warcraft has persisted since 2004, with little to no graphical updates. Cataclysim will introduce minor graphical overhauls, as well as a wealth of new features. What was left of classic World of Warcraft is gone. Almost every zone in the game is going to be overhauled. New quests will be introduced, some old quests removed, and everything streamlined for new level 1-60 players. Classic zones like Duskwood and Westwood are being revived. The nature of cataclysm is that everything in the world is going to change. Coasts are going to move inland, holes and wirlwinds from the plane of elements will break free, and everything you knew and loved about the original game will disappear.
But, that doesn't mean that the new changes won't be fun or interesting. They certainly will. For old players that have played for nearly 6 years, this will be a bitter-sweet expansion pack. The old world will be reforged, and the new world will be fresh of new quests and possibilities. Zones will shift and change, old NPC's will give way to new NPC's. The main evil of the world, the scourage, have been defeated. The Lich King is dead. This will be reflected in scourage zones like the Western and Eastern Plaguelands.
The undead mobs and worgon threat of Duskwood have been eliminated. Duskwood will now be more of a nature friendly mob enviroment. The defias threat of Westfall have been pushed back into the deadmines. Many of the territories they occupied will now be occupied by drifters and homelesss. Sentinel Hill has been turned into a minor city with a full questing hub. The broken bridge in Red-Ridge had been repaired. These are some of the changes you can come to expect. But, it will be reflected everywhere. Southshore, the human foothold in southern Lordaeron has been destroyed. The Forsaken unleashed the new plague there and transformed that city into a forsaken territory. Most of the Hillsbrad foothills have fallen to the Forsaken. The zone of Alterac Mountains is being incorporated into Hillsbrad Foothills as a sub-zone.
The Forsaken threat has been greatly enhanced in Cataclysm. Not only have they removed the last of the human refugees from southern Lordaeron, but have managed to create a foothold, beyond the Greymanne Wall in Gilneas. The new battleground in Catacylsm will be called the Battle for Gilneas. In which the Forsaken are attempting to establish a port in Gilneas, and destroy the last "human" kingdom of Lordaeron.
I highlight human because the citizens of Gilneas managed to survive the Scourage invasion of Warcraft 3, but fell to a plague that transformed them into Worgon. They join the alliance in Cataclysm representing the new Alliance race. The goblins have joined the Horde, making them the new race for the Horde factions. Both sides will have starting zones, but Gilneas is under seige by the Forsaken, and may lose their homeland to the undead afterall.
Not only will there be zone and quest changes, and new races, but there will also be a new villian. Arthas has been defeated, the new villian that has arisen to threaten the world is Deathwing. Deathwing has returned to the world and with his return the world has been forever altered, hence the name of the expansion pack, Cataclysm. There will be new zones in addition to Gilneas, such as Mount Hyjal and the Twilight Highlands. There will be new raids, and a new level cap 85.
All, in all this expansion is shaping up to be a must buy. I have even reactivated my account to explore the old world and prepare for the new. This game is looking very good. Enjoy!