When the iPhone was first introduced, Steve proudly announced that it ran Mac OS X. Some have speculated that it might be running some sort of "scaled down" or mobile build of the OS, but at the recent All Things Digital conference, Steve stated that it does, in fact, run "....real OS X."
Of course, this leads to speculation about future versions of the iPhone. If it's running OS X, perhaps widgets or other "desktop" OS functionality is possible. Are there any OS X features you'd really like to see on this thing? Let us know.