Except apples services category alone is more valuable then blackberry or Nokia ever was
I can't think of many other companies where they rely so heavily on just one product line. If iPhone unit sales drop but per unit profit increases, this will allow Apple to continue to paint a very rosy picture. If the unit sales continue to drop, we may see Apple looking to cut costs even further while increasing sales cost in order to keep the revenue numbers up. The problem is this is very much like a swan on a lake, everything above water looking great, everything under water going like crazy.
The moment that the iPhone stops selling the amounts they need due to market saturation or due to a competitor, then Apple is in the ****! Nobody thought Nokia or Blackberry could ever fail. This isn't an "Apple is doomed" post, but it would be folly to think they are too big to fail, especially when iPhone makes up more than half of their whole business.