International Game Technology (IGT) has acquired Double Down Interactive, a creator of social games that’s most commonly known for the DoubleDown Casino title. The Facebook-based app was one of the top four games on Facebook in 2011 according to official numbers, in addition to being the single largest online casino on the web. This added a lot of value to the merger.

IGT is shedding out a total of up to $500 million for DoubleDown: $250 million in cash, $85 million in retention payments that will spread across the next two years, and another $165 million if DoubleDown will meet certain financial goals.  In order to make sure the social game developer reaches the target earnings it will retain independence, and current CEO Greg Enell will continue to be in charge from the company’s Seattle headquarters.

“As technological innovations increasingly influence consumer behavior, social dynamics are quickly transforming entertainment and gaming experiences everywhere,” said Patti Hart, CEO of IGT. “The addition of Double Down launches IGT into a leadership position in social gaming, extends our global reach through new mediums, and leverages our unmatched expertise in game development.”

As a part of the transaction IGT is also gaining 4.7 million and growing monthly active users.

Online gaming has long become a multibillion dollar industry, with Facebook being one of the most profitable markets. But this space reaches far beyond the social network all the way into the cloud. A recent agreement between OnLive and Google will likely become a very big deal for Google TV: users of the smart TV platform will be able to enjoy media and interactive services they would otherwise not be able to access thanks to OnLive’s cloud-powered offloading. Google TV may be turning into the next Xbox, although from an entirely different angle.