A few former Apple employees have responded to a Quora question that asks, "What's the internal culture of Apple like?"
The answers are definitely interesting and including this comment by Chad Little on Corporate Culture.
Apple is a pretty divided mix of typical corporate red tape and politics mixed in with startup level urgency when the direction comes from Steve. If you have a project that Steve is not involved in, it will take months of meetings to move things forward. If Steve wants it done, it's done faster than anyone thinks is humanly possible. The best way to get any cross departmental work done was to say its for Steve and you'd probably have it the same day.