There has been increased chatter about this feature lately. Personally I’d love a feed-type feature for Publish. I think there’s a difference between updating a bunch of notes mostly meant for yourself and writing something for an audience. So, in my dreams, a Publish feed would be somewhat different from a firehose list of all the updates in a vault—instead it would give Obsidian users a place to put that audience-focused writing.
So, if there was a way to tell Publish to post “notes in this folder” or “with this tag” or “with this YAML metadata key” in a feed, it would be fantastic.