Pros: Good pay, if you negotiate aggressively. Good food. Good benefits. Location is good; California is a nice place to live, although expensive. Lots of exposure.

Cons: Management is constantly pushing you. You don't work at your own pace; you have to work at everyone else's pace. You need to stay after work every day and go to work on weekends. People are very egocentric, and their ego is entirely tied to how much code they write. I'm afraid of getting fired every single day.

Pros: Really smart people that care about building a great product. It's clear that people are really excited about what they are doing.

Cons: It's getting political and seems like there is a lot of jockeying. That's not great for an engineer who really cares about making a great product. It gets in the way.

Pros: - Free food - Reasonably good compensation - Reasonably flexible hours - Lots of smart, capable people - Work can be exciting

Cons: Working on product teams is trying because of the micromanagement of Zuck and other upper management. Many projects get delayed because they ask for random changes. Working on backend teams doesn't have that problem, but they are typically second-class citizens and don't get as much respect as frontend teams. Facebook is very large now and the bureaucracy is starting to accumulate quickly. It used to be that engineers could just do stuff, but now almost every change requires a great deal of pointless discussion or overhead. For instance, you now have to fill out a form just to log some data. Very strong focus on some of the "hot" product teams means that the rest of the company doesn't get preference with respect to product managers, designers, etc. Most frontend work is boring, mundane PHP. The only challenge comes from poorly-designed legacy systems. Managers will often ask you to work on something you don't care about just because it's a priority for the company. This goes against the claimed philosophy of Facebook, but it's the way things are trending.