years that Apple is working on ARM based computers with keyboards, after all the phones and tablets are already ARM processors. Recent rumours, talk about MacOS X, but Google's success with Chromebooks for education suggests another alternative.
I think Apple might make a low cost laptop running a version of iOS that would be perfect for users who want the simplicity and security of iOS, combined with lower cost and long battery life from an ARM processor. It would be popular with eduction but also the huge audience of users who find full operating systems confusing.
This laptop would have a keyboard and a large trackpad. My guess is that they would not do a touch screen as poking the screen on a laptop is not a good experience.
The whole idea is a reprise of a past product, the eMate, which was a laptop version of the ill fated but much loved Newton. The App eco-system would provide a rich set of applications that would need a little tweaking but port over quickly. Many apps already work well with external keyboards. Without touch presumably a "mouse" cursor would be needed but not much else.