Despite just starting today, there have already been several big announcements at BlizzCon 2010, including Diablo 3’s Demon Hunter Class, four free StarCraft 2 scenarios, and World of Warcraft: Cataclysm’s December 7th launch date. Here’s a little more information on Cataclysm:

It doesn’t get clearer than this: You’ll be able to purchase and download World of Warcraft: Cataclysm from Blizzard’s site (which will accomodate pre-orders soon) at midnight, Pacific Standard Time, on December 7th.

[via JoystiqVentureBeat]