Even Microsoft is coming to the conclusion that the multi purpose computer is not the bright light of the future but several specialized devices. That said Andrew Herbert, manger of Microsoft's Cambridge research center.
Ppl would be fed up to must learn how to use a device but are waiting for naturally usable devices.
The iPod might be a good example, many ppl are praising its ease of use, I personally never saw that as that big advantage (but this might be due to the fact that I *love* technical stuff). I have a simple agenda for mass market devices: When my mom can handle it instantly then it must be right

Disclaimer: my mom is a really clever person I respect most, but she was never too much into computers