When they offer you a job, it almost always comes with a bonus package payable each quarter over 2 years. I even interviewed there a few years ago and received that kind of package (which always comes with below market pay, plus a stock package which is often worth more than salary).
It's terrible because they way overwork people, and it is a super cutthroat environment. At the same time, they have very good people there, and accomplish a lot. It's amazing how they move their infrastructure along faster than microsoft, and are more nimble than google.
They also import thousands of young programmers, many of whom who are naive, from all over the us and the world. One friend who worked there for about 6 years said the core of good experienced people made it work, shepherding a large army of new people always coming and going.