I have taught my mom how to do certain things, but she has no intuition. As soon as something is slightly wrong or different, she gets stuck and can't move on. The solution is always something simple, like relaunching the app, installing an update, power cycling the computer, jiggling the usb cord, modifying the permissions on a file... but there are only so many contingency plans I can teach her.
Maybe I just suck at teaching, but I think that technical people have an incredibly curiosity and comfort with troubleshooting that people like my mom don't. We are basically playing on our computers.
With the iPad, my mom is finally playing too. She is really adept at it. Sending photos, checking facebook, downloading new apps, she was never comfortable doing any of this on the computer. Too many choices and settings and things to potentially screw up that she would be paralyzed, unable to explore and try things.
Ultimately I think the home button is the most important thing in the iOS ecosystem. If all else fails, go home and everything will be fine*.
(Unless your battery dies, or there is lint in the charging port, or your screen shatters, or you muted it, or you turned on airplane mode... it's not perfect...)