Today, I was part of a big announcement we made at Yahoo!: Zynga has signed a partnership agreement with us to bring its games to our network in force.

This is big. 80 million users play Farmville, on average, a month on Facebook. 28M for Poker. 23M for Mafia Wars. These users bring their friends and family along to build and tend virtual farms, whack mob bosses, and perfect their poker face. Zynga and Yahoo! both will actively promote their latest games on Yahoo!’s canvases, and Yahoo! in turn will build extensive hooks for all developers (ALL developers) to re-engage their users post-install.

Additionally, we’ll be working to expose new engagement channels to drive repeat usage of Apps in a way Yahoo! never did before: navigational links to a user’s favorite Apps and persistent requests on every page of our network. New places to play Zynga (and other) games. A far richer social graph than users have today.

My team, and the larger Yahoo! family, have been and continue to work around the clock to make lots of new opportunities open up for all 3rd-party developers. You can read more on my YDN post about the developer-facing components, as well as the TechCrunch scoop on the deal. It’s exciting to be able to share the news.