In 5 years, I would be surprised if hardware accounts for the major portion of Apple's revenues. I think it will still account for a major share of profits, but the revenues will come from other areas - primarily services and content.
Apple is already into iAd, and it is just a matter of time before they enter search to really compete with Google. It makes tremendous sense for Apple to enter search as a hobby. If nothing else, it will spook the shit out of Google.
Expect iTunes to become the iShop - a bigger and more diversified Amazon than Amazon.com. It will offer books, magazines, music, movies, TV shows, educational content, electronics, etc. But the other things will be even bigger - Siri based services like Ticket reservations, hotel booking, and possibly a foray into selling general products using Siri - basically everything under the sun, etc. It will also enter financial services in a major way with NFC based wallet. They will be forced to compete with Amazon to put pressure on Amazon in the tablet space.
At the end of the day, Amazon.com is a logistics game. And Tim Cook is a genius in logistics. Apple is going to do this, just to ensure that Amazon focuses less on the Kindle and more on its core business.