Vantaggi
Free candy
Free soda
Can call in sick whenever
Next to restaurants
Free alcohol sometimes
Svantaggi
I hear the NY, LA, and London offices are cool. SF is another story.
Cutting to the chase: they lie about your career opportunities. They'll tell you that after 8 months or so, you will be evaluated for a full time position. That is a lie. They only hire people full time after 2 years, or when they're desperate and trying to keep you. Otherwise they keep you on a contract. They also say they'll hire you as a Quality Assurance specialist but after you agree to the job, they'll call you an intern.
The team of interns is cool and friendly enough, but you're pretty much going to be ignored by upper management. You'll hear about people in the other offices being promoted 6-8 months after being hired (like they say you would be), but don't let that make you hopeful. The SF office doesn't care. There is no room for career growth. There's a reason there's such a high turnover rate.