• GMarks
  Helps you sync & manage your bookmarks with Google Bookmarks.
  in Public bookmarks with add-ons bookmarking extensions firefox gmarks mozilla sync
• Zinkmo
  
  Synchronize and share bookmarks and favorites across IE and Firefox.
  bookmarks explorer favorites firefox internet share synchronize
  in Public bookmarks with bookmarking bookmarks social_bookmarking sync tools by 8 users

bookmarking+sync from all users