Amazon

As mentioned in the title, I've only worked on one team at Amazon, and it is in the context of a new/secret project, so I'm not sure my experiences are representative of the company as a whole.

That being said:

• Fast pace
• Plenty of responsibility
• End-to-end project ownership
• Smart co-workers

• Not the most "positive vibe."
• Collaboration with other teams can be a bit adversarial (I guess this is a slightly less vague example of my first con).
• Work environment: open workspace (lots of interruptions), frequent moving (on a rapidly-growing team, anyway), dearth of conference rooms.
• Focus on code quality tends to lapse severely in the face of totally arbitrary deadlines -- and isn't usually accounted for at all during planning.