One step more meta: Should we create subreddits for topics that are discussed there, or rather for the style of those articles? An example of style could be a "Research" subreddit, where you post an article only if the statements it contains are referenced (or if it is self-contained original mathematical research).

An example of a division based on article styles could be:

• Announcements
• Research
• Best articles
• Articles
• Discussion

Official announcements = announcements about MIRI or CFAR activities, progress reports, advertising for effective charities, etc. Written by people from MIRI or CFAR, or by people who have their blessing to do so.

Research = trustworthy articles with references. It is okay if they are written in a less boring style and for a wider audience than the usual scientific articles (this is a blog, isn't it?), but if you say that "X is Y", you better provide some suport for that.

Best articles = no one posts their articles here. The articles here are the selected ones from the following subreddit:

Articles = you wrote a piece of text expressing an idea (not merely a question). It goes exactly here.

Discussion = all the regular threads; plus the articles that merely invite people to discuss a specific topic.