If you've ever watched someone pick up an iPhone for the first time and be able to immediately start using it (delightedly so), consider how some of those same people interact with a computer (double-clicking links in web pages, calling their browser "the Internet", having to deal with virus protection software, etc).

An Apple tablet might meet the needs of most people as a radically simplified "media device" to the point that they don't need to buy a traditional computer.