Blizzard knows how to craft some truly stunning cinematics. First there's the cinematic for the start of Starcraft 2, and now comes the intro movie for the new Cataclysm expansion pack. Interestingly enough, Blizzard worked the cinematic into a TV ad. Granted, it's not like they need to, given that World of Warcraft is the largest MMO ever made, but there's always room to expand, even if you rake in millions of dollars each month.
The cinematic in question shows a very irate Deathwing in some sort of underground forge, complaining about how he's so angry and pained and whatnot. Considering he is having molten steel hammered into his flesh, it's understandable that he's pissed. Queue footage of natural disasters befalling many different areas of Azeroth, and a finally in Stormwind. That's the entirety of it. The lines are cheesy, but Deathwing's been underground for so long that we can't expect much from him.