Last month was the anniversary of two #IndieWeb #distributedWeb building block specifications becoming @W3C Recommendations:
* 5y Webmention: https://www.w3.org/TR/2017/REC-webmention-20170112/
* 4y WebSub: https://www.w3.org/TR/2018/REC-websub-20180123/
Both specs are peer-to-peer mechanisms, Webmention for a site to notify another of a new or updated link to it, and WebSub for a site to broadcast (or subscribe to) notifications for when that site has published new content.

Bridgy is a good source of metrics for Webmention. The Bridgy stats from last June https://snarfed.org/2021-06-05_bridgy-stats-update-6 show steady growth in both total Webmentions sent and perhaps more importantly, unique domains sending and receiving Webmentions. In addition the number of implementations & support libraries continues to grow, interoperable across multiple languages: https://indieweb.org/Webmention-developer#Implementations

Webmentions still have interesting social and UX challenges. While spam has not (yet) been a major challenge, there is the larger challenge of how to semi-automatically moderate and/or prioritize handling webmentions received from others, especially people you have not met before. The nascent Vouch extension https://indieweb.org/Vouch has been prototyped and implemented on some sites yet needs some work to address the more sublte social challenges. There are challenges with even trusting and displaying the icons of authors who have sent webmentions. Pixelated icons https://indieweb.org/pixelated are one possible approach.

WebSub has shown slower growth. While the number of sites that provide WebSub notifications for new content continues to grow: https://indieweb.org/WebSub#IndieWeb_Examples the number of hubs and hub implementations have been fairly stable for the past year https://indieweb.org/WebSub#Hubs as well as implementations that consume WebSub notifications: https://indieweb.org/WebSub#Consuming_Implementations

The key next step for WebSub is more Reader implementations, e.g. in modern Social Readers https://indieweb.org/social_reader to provide realtime updates immediately when publishing sites post new content. Once there is broader incentive for more sites to provide WebSub notifications, consuming sites such as readers will have more incentive to implement receiving WebSub notifications, reinforcing a positive implementation feedback loop.

With the combination of Social Readers showing new posts in real time via WebSub and personal sites showing new comments & other responses in real time via Webmention, the peer-to-peer web will provide a responsive experience comparable to centralized social media silos.

Want to support Webmention and/or WebSub on your own site?

Drop by the IndieWeb Developer chat and say hi!

https://chat.indieweb.org/dev