We reported last week on Zynga launching a new social gaming platform appropriately titled the Zynga Platform. At the time, they only had a few small partners who would be bringing their games to the newly christened social games portal. Zynga now has three large partners that are going to use its portal to push their games.

Zynga announced yesterday at GDC that three large players in the social games arena – Konami, Playdemic and Rebellion – have joined up with Zynga to add their games to the Zynga platform. With these additions, Zynga cements their service as being one of the biggest players in social gaming outside Facebook.

“From Konami, one of the most esteemed game creators of our time, to the talented teams at Playdemic and Rebellion — we’re honored to welcome these new Zynga Platform partners. All three represent some of the best game development talent in the industry,” said Rob Dyer, head of platform partners at Zynga and former senior vice president of Publisher Relations at Sony Computer Entertainment. “Zynga Platform is about bringing great games to a captive audience that loves to play, and we’re dedicated to creating the best destination for social games for players and developers alike.”

Konami is one of the few Japanese developers, alongside Capcom, who have fully embraced the social gaming space. The company says that they have joined the Zynga platform to continue their success as a “top global social games developer.”

Playdemic has joined to increase the audience of its popular social games like Gourmet Ranch and Crossword Buddies. The company says that while it’s been successful on Facebook, it expects that joining the Zynga Platform will increase their growth even more.

Rebellion may be the oddest one out of the bunch as they are usually associated with core franchises on consoles like Aliens Vs. Predator. They reveal, however, that they are working on their first social game and will be using the Zynga Platform to launch it. I sure hope it’s an AvP social game in the vein of Mafia Wars.

When we reported on the launch last week, the new Zynga Platform Web site wasn’t up yet. It is now and open for play. Some of the current games available are CastleVille, Words with Friends and Hidden Chronicles.