Hopefully I'm posting this in the right place, but I see Reddit developments as Tech news right now.
Wanted to share a website that is tracking Subreddits that have/will be going dark. It even has a sound notification for when they change their status.
Also a good opportunity to back it up everyone with just not visiting their site. I've added 127.0.0.1 reddit.com old.reddit.com www.reddit.com mod.reddit.com i.reddit.com to my hosts file so I don't accidentally follow a link to Reddit (I think they have a lot more subdomains, so the hosts file based approach isn't perfect, but hopefully good enough for a quick solution).
i.redd.it and v.redd.it might make sense as well. There is a bunch of subdomains and other domains (…oauth.reddit.com, …redditmedia.com, …), but they are only used if you connect the the main sites (i. e., not hot-linked), so blocking those will be sufficient to block all reddit-traffic.