Pros
Free food: awesome food at the SF headquarters. Other satellite offices have food too but not even close to the HQ. They try to keep fresh fruit and juices everywhere. flexibility (depending on the team): if you are in a team like I am in (infrastructure) and the manager is cool about it, you will have the flexibility to work out of where you want. It really helps good benefits: Blue-cross-PPO or Kaiser, dental offered free for employees. free GYM at the SF HQ, frequent events with food&booze. good bonuses every quarter... particularly if you are in the game studios and you game does well.
Cons
Lacks direction. redundant work done a lot of times in the team. Upper management lets that happen. and some teams are working on things with no strong leads who can make strong decisions. Can't say is this is a common trend, since i have been here for less than a year. But i heard that there is a lot of shuffling of resources between teams going on all the time. No 401K matching. 6 weeks maternity leave, which is the shortest i have seen in companies.