Last week, Zynga entered the big leagues of video game marketing. To mark the launch of its Mafia Wars Las Vegas game, the company blew up a real armored car in the desert outside Las Vegas. It was an event worthy of Electronic Arts or Activision Blizzard, which have been known to do outrageous stunts in the name of marketing games.

Zynga says that more than 2 million viewers joined the live Ustream video of the event as rapper Snoop Dogg pulled the trigger that ignited the explosion of the 4-ton vehicle. In terms of live streamed events, Zynga’s was surpassed only by Ustream’s broadcast of Twilight: Eclipse in June.

The numbers rivaled prime-time TV viewership. Last Thursday, TV views of The Office and 30 Rock were 2 million households each. Zynga’s stunt was a bigger draw than Parks and Recreation (1.7 million households), Sportscenter (683,000 households) and Tosh.o (550,000 households). Zynga gave 631,000 users a free virtual armored truck in the game.

It will be interesting to see if Zynga becomes as outrageous as EA, which got into hot water when it ran a contest for its Dante’s Inferno game last year to get gamers to “commit acts of lust” with models working at the San Diego Comic-Con event and then submit photos via social network sites. The winner would receive a “dinner and a sinful night with two hot girls, a limo service, paparazzi, and a chest full of booty.” (EA had to apologize for that one).

It’s not clear how much it cost Zynga to blow up the armored car. But the company clearly feels it got its money’s worth out of the event. The video is available here.