The second batch of BlizzCon tickets sold out just as quickly as the first a few days ago, and if you didn't grab one you're just about out of luck.
Just about.
You can still attend BlizzCon, sort of. DirectTV customers can purchase the Pay Per View BlizzCon event for $39.95 which will allow you to be there, while also being at home on your couch. 2010 baby! Technology is amazing!
View the official BlizzCon site for additional details.