From Jean-Louis Gassée. First:
At Apple’s size, which is approaching $200B in yearly revenue, a “breakthrough” product would need to generate at least 5% — $10B — in order to move the needle. That’s approximately one Facebook.
As our friend Horace Dediu points out,iTunes by itself would rank #130 in the Fortune 500 list (yearly gross revenue of $23.5B, + 34% growth in 2103).