Pros
There are no solid rules about what your job is, so as long as you get your work done right you can kind of make it up as you go along. This gives a lot of flexibility to peruse the aspects of the job that interest you. People at Apple are smart and dedicated; they're there because they enjoy the work. The work is action, not talk, because there's no time to waste.
Cons
The converse of everything I said above is that there's an extreme lack of planning (positive spin: "Our company can turn on a dime!") or policy (positive spin: "Work how you want, when you want."). As great as flexibility can be, sometimes set policies are good so people actually know what to do. It sure doesn't hurt to make solid plans more than a few days in advance when a project has a 6-12 month schedule. Last-minute changes are the norm, and many a hair-pulling night has been spent cleaning up messes created by others' lack of planning.