Zynga Game Network, the creators of the popular online video games such as FarmVille and Cityville on Facebook, is proceeding on becoming another upcoming Internet initial public stock offering.The company was expected to file for an offering on Wednesday, according to sources.Zynga chose banks led by Morgan Stanley to underwrite the offering, according to the New York Times. Other underwriting groups also includes Goldman Sachs (NYSE:GS), Bank of America Merrill Lynch (NYSE:BAC), Barclays Capital (NYSE:BCS) and JPMorgan Chase (NYSE:JPM).Representatives for Zynga and the banks refused to comment.