It's not that I don't think phpbb is worth recognising - it is, and it's a great piece of software with a great development team. But the way they handled a security issue ( yes the linked one ) made me remove the link. They released a patch without saying it fixed a remote execution hole, the worst kind there is. So not many people updated as they didn't think it was that serious. And of course the people who deface phpbb websites use google to find them, searching for 'powered by phpbb' etc, or a specific phpbb version.