I first noticed it this afternoon while on the train on my way home from work. As far as I could tell from a quick Google search, they were trialling this in Australia and New Zealand with a few people already. I'm an Australian living in the UK for the last 5 years, so I'm not sure if they are expanding it out beyond the nest yet, or targeting me as an Australian?
Here's a link to what I screenshot: https://imgur.com/a/SJY6c6b
My personal feelings are that this is a terrible idea, and will lead to a lot of brigading and bullying. I'm really interested in hearing what DN think about this potential feature being released.
EDIT: Funnily enough, the upvote colour is blue, and the downvote colour is orange. The exact opposite of Reddit.