FarmVille Creator Not Leaving Facebook After All

Rather than end its strained relationship with Facebook, social-gaming outfit Zynga has opted to formalize it. This morning, the company, which had been rumored to be reconsidering its dependence on the popular social network, said it has entered into a five-year strategic relationship with it instead.

Under the vague terms of the plan, Zynga will expand its use of Facebook Credits–Facebook’s virtual currency–in titles like FarmVille and Mafia Wars, with the site presumably taking its standard 30 percent cut of transactions made with them.

In return, Facebook will–well, it’s not quite clear what the social networking giant will do, aside from allowing Zynga titles to remain onsite. Which, frankly, isn’t a bad deal at all considering that Facebook is likely responsible for most of the $450 million in revenue FarmVille is expected to generate this year.

Not that Facebook didn’t have something at stake here as well. Of the social networks 10 most popular apps, Zynga is responsible for six and more than 239 million Facebook members use them.

That said, the simple fact that many Facebook members actually play games like FarmVille and Mafia Wars suggests–to me, at least–that they’re pretty much willing to play anything, regardless of who developed it.

So maybe this is more a peace treaty than anything else, perhaps even one made to placate a mutual investor.