Pros
Zynga's pay is very competitive. Their facility is also great, with a big building, full kitchen, and parking (for a monthly fee). The perks are awesome. Great food served daily, prepared fresh. Sometimes they send you to Hawaii if your team does really well. Luxury Suite at AT&T Park. Great people at the IC level to work with. They're good at hiring team-level people.
Cons
Unfortunately, once you get up to the executive level things fall apart. The Corporate Leadership team seems constantly lost, often changing the "company vision", like drunk swerving on the road they just don't seem to know which direction to go in. Morale is consistently low because of that. They also have trouble getting games out the door. Everything is driven by PM's, so creatives usually get back seated.