Marketers trying to horn in on the conversations happening on the Web are paying closer attention to what many consider the ultimate prize: Facebook's user profiles.

On June 24, Facebook began testing a feature that lets users share their updates with the public—not just members they've deemed "friends." Each time a user provides an answer to Facebook's profile-page question "What's on your mind?," Facebook's software asks who may be allowed to see it. For instances when "everyone" is chosen, third-party companies are working on software that can analyze the information to see what products or services Facebook members might be interested in. And Facebook is modifying its search engine to look for these real-time feeds as well, the company has said.

How Many Facebook Users Will Go Public? - BusinessWeek