Vantaggi
I met some very talented, passionate folks that deeply cared about making good games. Get on the right team with the right manager and the right project - you could have a very good experience. And if you really care about little perks like free soda and LOTS of t-shirts, you'll find that too.
Svantaggi
The management is poor. What leadership says to the company often doesn't reflect what actually happens. They don't know when to kill a bad game pre-launch nor how to pick fresh ideas to enliven the haggard portfolio. They reward people for doing very short-term-gain things that hurt the games (and therefore, the company) in the long run. And worst of all: management never grasped the core need to make fun games, and make fun the priority. All game design decisions were trumped by the financial, and many good games were strangled to death by the management-mandated addition of "social features" and other revenue-based mechanics.