Now that Facebook has started the process of going public, it's getting serious about monetizing the service. The company has just announced that it will be adding new ad placements as well as a new type of ad to its desktop and mobile service. Starting today, ads bought through "Premium on Facebook" can be displayed in the mobile news feed; advertisers will also have the option to display content on the desktop logout screen starting April. Before, users would only see ads on the sidebar and the desktop news feed.

Facebook is also adding "Offers," a new story type that lets businesses share discounts and promotions directly through their pages. The company says that these ad tools can let a business reach 50 percent of its page's fans on a weekly basis as opposed to 16 percent without them. This isn't a huge departure from previous protocol, and it's certainly not one of the more controversial Facebook advertising moves, but it's a sign that the social network is finding as many ways as possible to turn its massive user base into long-term financial success.

Ellis Hamburger contributed reporting and photos to this article.