Daring Fireball has been digging into the saga of Tony Fadell, the "Father of the iPod" who's left Apple, potentially to be replaced by Mark Papermaster (if they can get around IBM's lawyers, that is).
What's been turned up?
The iPhone’s software is overseen by Scott Forstall (Senior Vice President, iPhone Software), and, at a technical level, Bertrand Serlet (Senior Vice President, Software Engineering). There is no such division between hardware and software with the traditional (pre-Touch) iPods. The story I’ve heard is that at the outset of Apple’s iPhone initiative, there was a heated debate within Apple as to what OS should be used. Forstall and Serlet pushed for using OS X. Fadell (and, according to one source, former Apple executive Steve Sakoman) pushed for using something else.1 Obviously, Forstall and Serlet won this debate, and, hyperbolic though it may sound, it may prove to be the single best early design decision in the entire history of the company. It seems hard to imagine the iPhone any other way now, but at the outset it was not a foregone conclusion that a stripped down and revamped version of OS X would work for a mobile phone.
And the OS Fadell is rumored to have wanted to use instead?
Needless to say, harnessing the already tremendous effort and technology behind OS X for their mobile wireless platform seems wicked-obvious in hindsight, as is avoiding the fragmentation of resources and focus that introducing a third OS (counting the already embedded iPod OS) would entail. However, the choice to go with OS X seems to have marginalized Fadell, taking him from the man behind Apple's music success, to the man behind the times on Apple's next great success, the iPhone.
And, hey, Linux eventually found a home on Android anyway!