*Update* It has been confirmed that the Canon EOS R will launch with an RF 28-70mm f/2L lens, and not a RF 24-70mm f/2.
As we mentioned yesterday, we're not going to be rating any rumors regarding the EOS R and we'll be publishing pretty much everything that sounds possible.
We're told that Canon will announce an RF 24-70mm f/2 lens with the EOS R body. The same source says the lens employs a “new lens design”, but gave no specifics.
A 24-70mm f/2 would obviously be a very large lens using conventional lens design, so we're not sure what Canon could change to reduce the size of the lens.
The same source also mentioned that the EOS R will only have one SD card slot.
As for the RF 24-70mm f/2, I'd be quite shocked if such a lens was in the pipeline.