Japan’s patent agency published a Canon patent application (via Canon Watch) that would see a touch panel on the side of a lens. Because people already have their hands there – especially for larger lenses, this makes a good bit of sense, preventing awkward reaches back to a camera’s back panel to adjust a touch control.
It might be one of the reasons Canon was confident its new RF mount’s extra contacts and control data flow would bear fruit in future lenses. When the RF mount was first announced, Canon engineers made a big deal about the increased potential for more information to go back and forth between body and lens.
The only benefits seen to date from this has been the control dial fitted to most new RF lenses, which is customizable in the camera settings; and additional gyroscopic data from the lens being pushed back to the camera to improve – sometimes significantly – the performance of the camera’s image stabilization.
With an additional camera control on the lenses, the increased bandwidth in the lens mount system seems to take on a certain critical mass of function, and quite possibly changes the nature of the equation going into decisions about buying third party glass versus Canon’s own offerings.