Oh dear…
Crossing my fingers for Canon's Professional Print & Layout.
I am one of those who can't stop myself from downloading the latest...!
Everything that I find important seems to be working fine, I use CPP&L and all seems fine in terms of colour...
However, and it is not the end of the world for me, Canon Accounting Manager does not work. (I use it to double-check the length of paper I have used at the end of a big print job)
What I have also noticed is that the Canon driver in Lightroom and Photoshop works better. None of the settings "stuck", previously including "Presets" - now they work.
One thing I have learned to do is to remove the Canon driver in System Settings before I download the new OS, then re-download and install it afterwards...
I have just made a print out of Lightroom and it was fine!