Zynga has finally announced their stock offering and they have filed their S-1 form. The publisher of social games like CityVille and FarmVille plans to raise up to $1 billion in a public offering.

The company claims that they have over 232 million active users every month. The revenue for the company has ramped up considerably in a short period of time, increasing from $19 million in 2008, to $121 million in 2009 and nearly $600 million in revenue in 2010.

“And now, by offering our shares to the public we hope to enable Zynga to invest more in play than any company in history,” founder and CEO Mark Pincus wrote to shareholders. “To accomplish this, we will continue to make big investments in servers, data centers and other infrastructure so players farms, cities, islands, airplanes, triple words and empires can be available on all their devices in an instant. We will also continue to fund the best teams around the world to build the most accessible, social and fun games.”

Zynga does admit to some difficulties, such as a dependance on Facebook and an agreement that expires in 2015. The company has also been mostly unsuccessful in the mobile sphere and admits it is “difficult to know whether we will succeed in developing commercially viable games for mobile.”

The social game developer has also been involved in intellectual property battles. Zynga does not expect to lose such cases, but they are costly in any event.

Source: AdWeek