Pros
Everyone there is very competent -- no one coasts. The senior management is extremely capable, and the company is completely focused on everything making a profit, sometimes to a fault. The food at the cafeteria is reasonably good. The best thing about the company is its dedication to making great products (that may sound like I'm regurgitating "the kool aid", but it's the truth); the company focuses on making things as good as they can be (while still eventually shipping a product). Lastly, the benefits are pretty great: the health plan includes dental and vision, and there's a stock purchase plan for employees.
Kontras
As above, there is extremely little R&D, if that is your interest. Also from above, every part of the company makes a profit *including the cafeteria*. This is not a company likely to get a free menu (like at several other Silicon Valley companies). Additionally, the culture of overwork pervades Apple as it does many Bay Area technology companies. I have many friends there that can not be relied on to be available on weekends. Lastly, Cupertino is not a particularly fun place to spend time. It's by far the most suburban and sprawl-y of the cities and towns in the Valley.