With CTAP 2.2 nearing completion, changes are coming to MDS as well, e.g., support for new values, the addition of a simpler blob to help RPs provide a better UX for passkey providers, etc. To make sure you know what's coming and when we've added a form to the main MDS page (
https://fidoalliance.org/metadata/) so you can sign up for MDS announcements.