Announcements (in this Discourse forum) is one of the places that is still missing the August 13th release of the 5.1.3 version. (And it takes a LOT of searching to discover the difference between the 5.1.3 and 5.1.3-2 for Windows.)
Perhaps there an RSS feed for version announcements? There’s a somewhat dated RSS To Topic plug-in for Discourse.
The Headline News is usable for a ‘pull’ announcement system but not so much for a push. (I imagine that 150 plug-ins mean that those update notices would incessantly flood an RSS feed.)
Official announcements are also on GitHub, the HeadlineNews gramplet, the maillists (devel, user & announce), the WordPress blog, the MediaWiki pages (download page, changelog, Roadmap), the MantisBT buglist, this Discourse forum. (What others?)
Announcements on the user list normally come after the Download page has an installer available. The “build your own from source” is the first release.
The anxiousness about the 5.1.3 AIO installers preempted that thread.