It's not about <i>needing</i> a simpler computer.  It's about <i>wanting</i> one.  Not all people; not even all mothers or grandmothers.  And not all the time.<p>The iPad has, in a sense, already made it.  It, despite some people's protestations, <i>is</i> just a big iPod touch.  Whether this form factor works or not, people have responded extremely well to its abstractions and simplifications, despite the limitations.