Previously, there was no way to read RSS feeds for Editors Only Manila sites in an RSS news reader, because Manila uses a cookie for authenticating membership.
This feature enables basic HTTP authentication for the RSS feeds in Editors Only Manila sites, so that any RSS news reader which supports subscribing to password-protected feeds can be used to read the RSS feeds in Editors Only Manila sites.
If you run a Manila server and would like to help test this feature, please follow the instructions in this message on the Manila-Dev mail list.