People in the industry whisper stories about Zynga like cautionary tales, and most of what they say is correct. It's a dysfunctional company caught between its start-up roots and a burgeoning traditional American corporate culture. There's a huge disconnect between the corporate-oriented aspects of the business and the game-making oriented aspects of the business. It's possible to slide into a job at Zynga and be ignored for *years*. Opportunities to advance are uneven or plateau quickly. The company won't hesitate to can your project even on the edge of completion. Shipping a game at Zynga is a constant challenge—I know people who worked on several different games teams for 5-6 years and couldn't put a single shipped title on their resumes.
All that said, every department and every team is different. I had great managers in a department that lacked direction, but that didn't make up for the overall low pay and inability to advance. People might go to bat for you when necessary (like anywhere else), but their ability to change your circumstances are limited. Managers caught in the middle have very little power and are getting pushed around just as much as folks lower on the ladder.
It can be very challenging to make lateral move into a new role if you decide you want to be involved in a different aspect of game development. Don't be afraid to befriend your team's upper managers and HR Business Partner—having them on your side can go a long way toward you receiving the bonuses, raises, title changes, etc. you need to advance your career.
Bottom line: complacency will kill your career at Zynga. The best way to survive a dysfunctional company is refuse to engage in the dysfunction. Come to the business hungry—with strong goals and a calculating, looking-out-for-#1-attitude—and do everything you can to meet them. Then, leave.