Pros: Free food, good work-life balance.

Cons: I believe there is a quota to meet for manager people, regardless of their performance. I was the only engineer working on a cross-company project with Yahoo Japan and was let go without notice to my manager, as well as the business director on the Japan side. My manager was shocked to hear the news from me rather than someone higher. Also, someone was let go on Friday and re-hired by the manager on the next Monday. (Some VP from another team laid off the guy, and his manager tried hard to bring him back. I know it's a mess.)

Pros: Free food, shuttles, gym, cafes, nice laptops, and some VERY smart people. No QA, so everyone's a dev and responsible for their work.

Cons: Horrible culture, work environment. The cliques rule, and they cover for each other. The old timers use newbies and H1s. There's little opportunity for advancement. Speak up for yourself, or you will get railroaded.

Pros: The people there are all smart and have a passion to work, and are easy to communicate with.

Cons: The senior management team is not steady and always changes during the years.