Pros
Intellectual growth - The company spends a LOT of effort in growing the employees intellectualy. I, personally, get to go to conferences, consortium meetings, universities, etc., to build my knowledge and network base. There is a lot of freedom to take courses, purchase books and journals which contribute extremely favorably to intellectual growth. We collaborate with the academics to stay fresh with the latest technological developments. Collaborative atmosphere - The company has lots of events where we get to see each other's work. There are a ton of web-based tools wherein we can collaborate with people with similar interests. The management also supports collaboration (sometime not, due to political reasons) and team work. Heavy emphasis on technological breathrough - A lot of work we do is cutting edge stuff. Though PG might look like a marketing company from outside (and inside, sometimes), some of the work we do is so advanced, that even the researchers at top universities haven't figured it out. I recently went to a new hire event, I was completely amazed at the technology we use in various aspects of developing new products, processes, and understanding the consumers. I have never taken a bar of soap for granted, ever since. People are inherently very nice - It begins and ends with people in the company. I have been pleasantly surprised by how friendly, honest, and transparent most people are in the company. I have been able to approach the vice presidents in the company with the same candor and informal attitude as with my peers. The discussion is not always business - it can be about movies, cars, sports, make-up, dresses, etc.
Cons
Sometime, the bureacracy can be debilitating. It may be because of the company rules and regulations, or because of the local culture of a particular office. The work hours can sometimes be long, and striking the work-life balance can be difficult. But it really depends on the individual and how they want to allocate their priorities.