In January we introduced Google Social Search to help you discover relevant web content published by your friends and broader network of contacts. Since that time we’ve worked to steadily improve our comprehensiveness using public URLs and data on the web. Today we’re expanding Social Search using additional links that appear in the Buzz tab of your Google profile.

If you’re signed-in, Google makes a best guess about whose public content you may want to see in your search results -- the content you see comes from your “social circle.” Your social circle includes a variety of private and public connections, such as the ones surfaced through links that appear on your Google profile. To improve social search, we’ve started following a more comprehensive set of the public links from your Google profile to populate your “social circle” and to find social content.

Here’s how it works: If you use Buzz, you have the option to add “Connected Sites” and post content from these sites publicly on your Google profile. For example, you can choose to connect your Twitter account and set your tweets to appear publicly in your Buzz stream and the Buzz tab of your profile.

With our enhancements today, we’ll start following these public links in the Buzz tab to improve your social search results. That means if there’s a link to your Twitter account in your public Buzz stream, we’ll follow that link to add the people you follow on Twitter to your social circle. If you don’t use Buzz, you can still add links to YouTube, Picasa and other sites directly to your Google profile, and we’ll continue to follow those links as well.

As before, all the content that appears in Social Search is public, and only you can see your private connections. You can see exactly what content you’re sharing and who you’re connected with by clicking “My Social Content” and “My Social Circle” next to any social search result. To learn more about Google Social Search, please see our help center.

For our avid Buzz users out there, we hope this improves your social search results on Google. In the future, we’ll continue to improve social search using links that appear in Google profiles. The changes are rolling out now and should be fully deployed by the end of the week. As always, you can click “more search tools” and select “social” to see more results from your network. Try it out, and give us feedback.

Posted by Mike Lopyrev, Software Engineer

As the web becomes more social, more people want to share information with their friends and colleagues across a wide array of services. While most of these services provide APIs to facilitate sharing, the ever-increasing number of these services with unique APIs makes integration costly for publishers and limits the likelihood that lesser-known services will be supported.

OExchange, a new protocol spearheaded by Clearspring, aims to address this problem by specifying a conventional way for publishers to "offer" links to sharing services, and for sharing services to design their API endpoints.

OExchange also provides a mechanism for publishers to discover information about new services that they've never seen before using a format called XRD on top of an emerging protocol called host-meta, which happens to benefit from XAuth as well.

We're happy to report that the Google Buzz sharing API (which powers the Google Buzz Buttons) has supported the basic model of OExchange since it was first released.

As we announced the launch of Google Buzz, we are committed to adopting open protocols and technologies that promote interoperability and intend for Google Buzz to be a good citizen on the social web. OExchange is a promising effort that seeks to simplify and make sharing easier for publishers and service providers alike. We invite you to read over the quick start guide, technical specification, and try out the helpful tools that Clearspring has prepared to make supporting this technology clear and simple. Your feedback is welcome on the OExchange mailing list.

Posted by Chris Messina, Social Web Developer Relations Team