Two phone interviews. First one was very unstructured. One technical question, some management questions.
Second interview was more structured, similar questions.
Based on the two experiences Zynga has a fairly rigorous process for interview scripts, or else there's a lot of groupthink going on among software managers. Definitely smart people though, and enthusiastic about working (long hours) for the company. They both mentioned great morale among all employees and low turnover. Maybe partly because the IPO was coming.