As bedfellows go, Microsoft and Facebook have had something of an open relationship; a knot of social / search entanglement that recently yielded Graph Search, among other crossovers. But, as of today, the two companies are looking to take things even further by building upon the work started with Bing Tags last summer. The integration, which previously allowed users to tag themselves or Facebook friends on sites and search queries for more personal feedback, will now extend beyond a user's inner circle and be made available to a "broader audience." Of course, privacy here is key (as we also learned from Facebook's last press event) and Microsoft's making it abundantly clear that this is opt-in. So, unless you give explicit approval for your tags to appear out-of-network, they won't -- only your friends will have access to those results. If you haven't already signed-up for the beta service, you can test it out at the source below.