Your Facebook content may soon find its way into ads on the social network.

Facebook unveiled details yesterday about a new advertising initiative called Sponsored Stories. The effort allows advertisers to find mentions of their brands--either through Places check-ins, recommendations in a news feed, likes, or actions in a Facebook application--and repurpose them as advertisements on the site.

Screenshot of Facebook&39's video featuring Sponsored Stories.

Facebook said that if a person currently checks in at a respective company's store or "likes" a brand page, the action often gets lost amid all the other content a user's friends may see. Sponsored Stories solves that problem for advertisers by plucking valuable content from user news feeds and making it more readily noticeable to others.

Facebook is charging advertisers on a CPC and CPM basis. The company was also quick to point out that at no time will it make a user's personal information available in a Sponsored Story.

The Sponsored Stories, which kicked off yesterday for Facebook's "premium" advertisers, will be labeled and viewable only to the content creator's friends, Facebook noted. The service will respect a person's privacy settings. However, Facebook users won't be able to opt out of the service. That's somewhat surprising, since Facebook users can modify their inclusion in the company's existing Social Ads by letting their social actions be included in a marketer's ad on the site and be shown to friends--or opt out.

In a video, Facebook talks up the word-of-mouth aspect of Sponsored Stories. The company said people want to know what their friends care about and that friends' opinions have more authority than a simple ad from a company trying to market its products.

"When we make decisions about the products we want to buy, the places we want to go, we're basically looking for cues from our friends about what those things should be," Facebook product manager Kent Schoen said in the video. "And all of us aren't out there trying to market ourselves or trying to influence people to go somewhere or do something. But the reality is, when we make a decision, we're looking for information. And we want that information to come from people we trust."

Inevitably, comparisons will be drawn between Sponsored Stories and Twitter's Promoted Tweets. At first glance, they are somewhat similar because they both use content on the respective social networks. However, unlike Sponsored Stories, Promoted Tweets feature content created by marketers, which is then advertised on the site.

Even without help from Sponsored Stories, Facebook's advertising revenue continues to grow by leaps and bounds.

According to a study released earlier this week by research firm eMarketer, the social network generated more than $1.8 billion in ad revenue last year. The research firm expects that figure to jump to $4.05 billion this year and reach more than $5.7 billion in 2011.

Updated at 12:01 p.m. PT to include more details on Sponsored Stories.