Cataclysm revamped most of the old world zones in Azeroth, updating them for a post-Arthas world. While waiting for the expansion to officially drop, I began two of the new race/class combos -- an undead hunter and a dwarf shaman. The undead starting zones, starting with Deathknell all the way through the end of Hillsbrad Foothills, completely engaged and delighted me in their use of driving storyline, humor, and curiosity as to just what in the world is up Sylvanas' sleeve? Everyone should create a new undead character and experience these quests. At least go to Hillsbrad Foothills and do the chain that starts with you being a "quest giver."
On my dwarf shaman, things were going along smoothly, pleasantly -- no real outstanding quests, but no real duds either -- and then I got to Menethil Harbor. First off, the sheer devastation in the town itself is pretty eye-opening. Go swimming down around where the town used to be before it got flooded -- it's crazy. Then I talked to a familiar character sitting outside the inn who told a familiar story and had me go on an awfully familiar quest -- First Mate Fitzsimmons, who asks for a beer to embolden him, and then you go kill ghosts at the Cursed Fleet. "Hmm," you think, "wasn't this solved already for the past six years?" Yet you still go and complete the quest, because it's money and experience, and you turn it in expecting the same old, same old.
And then Blizzard throws a total left curve you never saw coming and which I will not spoil for you here, because you must go do the quest right this second if you haven't yet. It will blow your mind.
So which quest chain has astounded you so far?