I just installed Firefox 3 and lost many of my bookmarks. For some reason, it didn't like sub-folders. If that happens to you, delete all the current bookmarks it shows (it'll duplicate them if you don't) and navigate to:
C:\Documents and Settings\Profile Name\Application Data\Mozilla\Firefox\Profiles\91nbplz3.default\boo kmarkbackups and choose the latest date and import them over as a html file.
Problem solved
