Hello Gareth
The interesting thing about IPv6 is that it has been used, in experimental scenarios so far, to address things other than interfaces or NIC cards. Some research institutions are experimenting with addressing particular pieces of content. So the photo you upload of yourself on Instagram could be assigned an IPv6 address and can be uniquely located by anyone on the Internet simply by using that address.
Online videos have been separated into 2MB parts, each of which is assigned an IPv6 address, and you can view that video just by using a text file script with a list of the sequential IPv6 addresses that correspond to all the parts that comprise that video. In this way, all the parts of the video can be downloaded in real-time from various geographical locations, depending on where you are physically, so that the video can be reassembled and displayed on your screen in the most efficient way possible.
So you see, IPv6 is moving away from IPv6 address per device, or even per interface, and is being assigned to objects and things that you never would have imagined using IPv4.
Just some interesting stuff that’s going on.
I hope this has been interesting!
Laz