The "export" feature is now available. You can export your subscriptions in OPML format by clicking on "export" in the "Manage My World" page. The export button is located next to the "Import OPML" button in the "Manage Feeds" box. I circled it on the picture.
Once you click on "export", you'll be prompted to save or open the OPML file. Select "save" and choose a folder for the file. You'll be asked for this file when importing your subscriptions into other readers.
Please leave a comment or email me at support at searchfox dot com if you have questions.