Under the new terms, Zynga games will be under Facebook’s standard terms of service starting March 31, 2013. Zynga won’t have to display Facebook ad units or use Facebook credits on Zynga.com games, as it had to.
Facebook and Zynga had previously agreed to a deal in which included, among other things, Facebook agreeing not to develop social games in exchange for Zynga using Facebook as its exclusive platform for certain games.
Zynga gets opportunity to operate their own standalone gaming website, but gives up its ability to promote its site on Facebook and to draw from the thriving social network of about 1 billion users.
Both internet companies have been trying to reduce their reliance on each other, Zynga wants to start its own Zynga.com platform, and Facebook want to work with other games developers. This could be a very bad move for both companies as Zynga games is a big draw for Facebook and Zynga is now competing with other games and game sites.