Today Zynga announced the launch of CityVille+ on the Google+ game platform. CityVille, which allows gamers to construct and build a thriving metropolis, is the most popular game on Facebook.

Zynga is the world’s leading social game developer with more than 230 million monthly active users playing its games which include CityVille, FarmVille, Empires & Allies, FrontierVille, Words With Friends, Mafia Wars, Zynga Poker, Cafe World, and Treasure Isle.

The addition of CityVille is a big deal for Google. Google+ currently has 18 games, including Angry Birds, CityVille, Crime City and Zynga Poker. Is FarmVille+ next?

So what are you waiting for? Sing “We built this city…. We built this city” on Google+.