Pros
Working for Apple is best if you like having a peer group to learn from and grow with. You get out of Apple what you put in. You really can't be a super rock star to it alone type, since the process of creating a product requires many hundreds of people. An individual can come up with and promote their own idea - and then see a support group grow around it if the executive team decides to productize it. This is quite different from other companies where individual contributions are not respected nor desired. Apple lets you be creative, and rewards that.
Cons
The biggest downside to working from Apple has to be the overcrowding on the main campus. They're building another campus, and they've leased a bunch more space, but new hires are starting to double up and the on site cafeteria has become a madhouse. Apple no longer has a sabaatical program, which is something I'd hope they bring back in the future. With the economy being the way it is, Apple holds the cards as far as compensation, but I really have no complaints. They recently improved the coffee situation too. I wish they had a better employee purchase program.