Pros
Great benefits, working at a company everyone respects and says "wow" to, getting to help build the products that really are changing the world. The hours are reasonable, you are treated as a human being and respected as an engineer, and the on-site breakfast lunch and dinner are unmatched anywhere. Luckily google makes their billions using only a small fraction of their total workforce, leaving lots of capital available to dedicate resources to other projects that aren't purely motivated by short-term profits (but rather those that help build press for the organization and are theoretically interesting and innovative at the same time). Tech-talks about a whole range of topics not strictly required for you to carry out your job responsibilities but just for your general education are a huge plus. Google employs some of the most innovative thinkers and builders of our time.
Cons
Very large organization. Seemed to provide fewer job advancement opportunities than I was looking for. Little project ownership (feature ownership perhaps, but typically the project involves many many people). In my case, the project had three different managers who worked out of two different offices, leading to lots of confusion.
