If you've been away for a while and have your News Feed sort set to "Sort: Highlighted Stories First," you’ll see the highlighted stories at the top of News Feed. They’re marked with a blue corner and may be different depending on how long it’s been since you last visited your News Feed.
We determine whether something is a highlighted story based on lots of factors, including your relationship to the person who posted the story, how many comments and likes it got, what type of story it is, etc. For example, a friend’s status update that might not normally be a highlighted story may be highlighted after many other friends comment on it.
We've also added a control in the top right of each story where you can add or remove the highlights from a story. This will help us improve your News Feed over time. If you see something that isn't interesting in highlighted stories, hover over the right side of the update in question, click the arrow and click "Remove Highlight" from the menu.