A world without Flash

[nomko]

a) Does this mean pepperflash-non free is also on the way out.

Don't think so. Pepperflash is a NPAPI maintained by Google and newer than Adobe Flash Player. While Adobe dropped support for their Flash, Google keeps maintaining it for the Chromium project of which Google Chrome is forked from.

b) What happens in the switch over period where "millions"? of sites become un-usable.

Sites that still uses Flash will not be blocked, as said by Mike, you will get a prompt asking what to do. This action of Google will eventually "force" those "flash-sites" to ditch Flash in favour of HTML5. But this will take some time also to rebuild those websites.

c) The repository hosts adobe-flash plugin- is this now safe? should it be used as all?

Adobe Flash was, is and will never be safe. That's why it will be blocked completely by time. Adobe does not support their Flash version for Linux but it will keep receiving security updates. But this will stop also by time (i thought is was till 2017??).

d) What are the ramifications for LL?

All distro's will follow the path chosen by Google and also by Adobe. There's no reason to stand up and fight against these decisions. And for what reason? If you need Flash, use Chromium with pepperflash plugin for the time being.