Pros
Retirement Plan, Ability to Contribute are top notch. If you have the drive to behave like you have 100% discretionary time, and work on things which are high risk but high reward for the company, you will thrive. The people are top notch, and you can learn a lot in the first five years and if you don't like it, move on. AG did a survey among people who left the company and those who were forced out for being too radical had a net worth of 3x those who left voluntarily, so it's a great place to get run off from.
Cons
Difficult to turn performance into promotion. There is a lot of credit grabbing, since this is a promote from within organization. As my country friend tells me, when there is an ear of corn, all the chickens come running. If you can't work in a way which makes your contributions to the most important things obvious, don't expect a reward. Unfortunately, the same is true with relationships. P&G does hire excellent people, so the competition level is very high, and managers naturally gravitate to promoting people they like and who are their friends, insted of it truly being who made the contribution.