Call of Duty: Black Ops II has generated a lot of buzz since its unveiling on May 1 during the NBA playoffs. Activision Blizzard’s latest entry in the blockbuster video game series generated four times as many messages on social networks, according to market analyst Nielsen Media.

The firm tracked only 4,911 messages about Call of Duty across a number of social media sites — Twitter, Facebook, YouTube, blogs, and boards — on April 30. The number grew to 21,454 messages on May 2.

On YouTube, users have viewed the launch trailer 7.1 million times. This morning, the video has 70,954 likes and 25,085 dislikes.

Retailers started taking preorders for the game yesterday.