Having used an early kindle and a recent kindle, they are incredibly similar. One of the main innovations of the new models appears to be adverts you have to pay to get rid of.
Also gradually phasing out support of formats like mobi, in such subtle ways that if you open a mobi file you cannot go back to the library, but have to cold-reboot your device... My current kindle is my third one, and is the last. I will never ever pay for a kindle to Amazon, due to its user hostility. Oh, and also you cannot move ebooks between accounts, even not with a lot of friction, eg. support tickets, which w…
Just US and UK have family accounts.