That doesn't say much for the avg intelligence of an iphone user though. (that was a joke in case people wonder.)
I can see the truth in that. Hodapp's friend's 2 year old can use it, yet the lines of people at the Genius bar never end. I've only been in an Apple store about three times in my life and already I've heard some of the most ridiculous questions imaginable thrown around by the morons inside. My favourite one by far was a woman asking where "the button that turns the headphone socket off" is located.
I like the simplicity of their UI but I would be for landscape orientation. Often if I'm switching between reading, web-browsing and gaming in landscape I don't bother to rotate my phone and instead rotate my head.
I enjoy the simplicity of IOS, so my proposed changes are minor: Landscape option A setting to lock landscape Better handling of alerts (e.g. only show on home screen)