Zynga Game Present at Google+
Google and Zynga previously had worked since the early launch of Google + Games. Google is an investor in Zynga, and when the gaming platform was launched in August, one of the 16 games that launched one of them is the 'Zynga Poker' games.
Previously, CityVille have been getting more traffic to Facebook than Zynga poker games output. Besides that, CityVille also has more than 70 million users each month, while Zynga Poker only has approximately 30 million users.