Apple has filed for a patent (number 20170147087) for “housing as an I/O device" that hints at, among other things, a Mac laptop with a virtual keyboard.
The invention would sense user interactions with the exposed surface of the device and generate electrical signals based on the interactions. Those signals could make a virtual keyboard appear.
They could also cause icons to light up when speakers are activated by a tap so you could control volume (something already implemented in the MacBook Pro with Touch Bar).
The invention could also offer certain information when device is in sleep mode, graphics within housing may be used to give limited information without waking the device up. For example, the housing may provide an indication of remaining battery life or an indication of a wireless communication signal strength.
A tablet is also mentioned in the patent filing, so some of these features could make it into future iPads.
By the way, check out this MacBook Pro 2018 concept that explores the integration of a full-size touchpad in place of the traditional keyboard. It relies on Apple’s own Taptic Engine system to give the user the feel of physical buttons or even emulate a scroll wheel or sliders. It retains the touch bar for shortcuts and function keys but the entire surface is touch enabled.
Here’s Apple's summary of the invention (for the more technically minded among other readers): “There are provided systems, devices and methods for operating a housing for an electronic device as an input/output (I/O) device. In one embodiment, an electronic device includes a housing configured to function as an integrated housing and I/O device and one or more sensors obscured by a panel of the housing.
“The one or more sensors being configured to sense via the panel of the housing. The electronic device further includes a processing unit communicatively coupled to the one or more sensors and configured to interpret electrical signals generated by the one or more sensors. One or more output devices are communicatively coupled to the processing unit and configured to provide an output in response to the one or more sensors generating an electrical signal.”