OPML is/was criminally underused. I think that lies at the feet of Wordpress. Early Wordpress supported a blogroll but needed a plug-in for OPML support. Wordpr

OPML is/was criminally underused. I think that lies at the feet of Wordpress. Early Wordpress supported a blogroll but needed a plug-in for OPML support. Wordpress then moved blogroll support before finally removing it. The (arguably) most popular blogging system ignoring OPML meant feeds were much rarer than RSS. The rarity of OPML feeds kept them from getting any native browser support. Most of the time you only see them as a way to import/export a list of feeds from dedicated RSS readers.