I think this is a great idea indeed

To enable this, we intend to augment our current tag-based organizational structure for posts
with a new system called “communities”, a special group into which others can post articles.
Two types of communities will exist: communities into which anyone in the world can post
(where community founders (or their delegated moderators) can decide, post-hoc, which
posts to hide from view) or communities in which only community founders’ (or their
delegated authors’) posts will appear.