On the CNET Digital Media Blog author Dara Kerr reports that Facebook has begun inserting ads into Facebook Users News Feed stream. While ads on Facebook are nothing new, this is a different approach as the ads used to be in the 'Stream' at upper right side of the page. These sponsored ads will appear in your regular news feed.
As Dara suggests:
To figure out whether a post is legitimate or an ad, Facebook users can hover their mouse over the word "featured" and a black box of text will pop up saying, "A sponsor paid to feature it here." The only way to get rid of the ads is to click the "x" on the right corner of each post, deleting them one by one.
You can read the full article here: Facebook inserts ads into users' news feeds