Dpreview published their Sigma CEO interview. And there is a lot of interesting info but I am only reporting two of them here:
This is what he said about the mirrorless future:
Within three or four years I expect our mirrorless mount lens sales to be much bigger than for DSLR. Maybe 70% to 30%.
This is what he said about the Canon EOS-R
The 50mm F1.2 and 28-70mm F2. Very impressed – and a little jealous! They’re possible due to the wide diameter and short flange back. Otherwise such lenses would be very difficult or impossible. Having the larger elements at the rear of the optical system makes it easier to achieve good performance at large apertures.
He confirmed indirectly what Leica manager said about the E-mount…it’s really not optimal for lens design.