When I read on Erik's blog that Sage 1.3 was released with Live Bookmark support, I was ecstatic. I immediately converted all of my RSS feeds from normal bookmarks to Live Bookmarks (it was as simple as editing bookmarks.html - the file where Firefox stores your bookmarks - and changing all incidences of HREF to FEEDURL in the section of the file where my RSS feeds were located).
Sage now interprets Live Bookmarks just as it does regular bookmarks, allowing the user to subscribe to feeds using the auto-discovery mechanism in Firefox.
With Live Bookmarks, this "update" behavior does not occur. While Live Bookmarks appear "normally" in Sage's sidebar, there is no integrated mechanism for updating them. As a result, one must either manually update each Live Bookmark (by right-clicking on it and selecting "Refresh Bookmark") or remember which of their RSS feeds are Live Bookmarks (as opposed to standard bookmarks) and double-clicking on them, which would display the RSS items in the Live Bookmark's feed in a submenu.