I believe that the current Apple Macbook is a great product and has few design problems. It is a great starting point and has many features that could be added onto it. One ability that the current Macbook is lacking is the ability to be easily integrated into other electronic devices.
First, I would make it so you could wirelessly sync your iPhone or other smart phone into it. It would connect via bluetooth and you would be able to transfer data and music more easily. There would also be a program or application that would be a kind of interface for the link. It would give you the option to backup data on both devices. It would also allow you to take music off of your phone (or your friend's phone) and put it on the computer. This feature would make the synchronizing of your phone and computer much easier and more efficient. It would also eliminate the need for an extra cable.
The next feature would allow the computer to use a phone (most likely an iPhone) to access the internet from anywhere. Although this is currently possible, you need to have a device that will allow you to use the phone companies' network. This innovation would allow you to connect to the internet more easily. There would be no need for an extra device and you would not need to add any extra data plans onto your current phone plan.
The last innovation that I would add to the current Macbook would be the ability to automatically sync with your home entertainment system. You would be able to wirelessly connect to your T.V., sound system, DVR, and home computer. You could more easily use a T.V. set as you computer screen with no cables, and music etc. would play through your stereo. You could also sync and backup with your home computer easily. If synced to a DVR, you could transfer shows onto your laptop and watch them anywhere you go, and by connecting it to a wireless mouse and keyboard and using a TV as a monitor, you could completely eliminate the need for a home computer/Desktop.
I think that people would easily adopth this new technology. Life would be so much easier if we could eliminate or combine devices. Also, the elimination of cables in other electronic equipment could be made possible by this new technology.