So what determines who's activity will show up on your news feed? And how do you know your activity is showing up in your friends' feeds? Facebook actually has a formula to determine this very thing. It's called EdgeRank:
I found this image from a blog by Jason Kincaid, written for TechCrunch.com. He breaks down and explains this formula better than I can, so be sure to read his article too, found here.
In a nutshell, the formula considers 3 things:
1. The amount of interaction between who posted the item and who is viewing the item
2. What type of activity it is (comment, like, share)
3. Time-how long ago the item was posted.
If you are using Facebook for your business, this demonstrates the importance of engaging with your Facebook fans. The majority of people who "like" a company or business will never re-visit the company's page. So how do you get your info in front of them again, and (hopefully) get them back to your page? You MUST get seen on their news feed.
Follow the formula. Engage! Interact! Encourage your fans to comment by asking questions. Ask people to share your posts. The more interaction between you and your fans, the more likely you'll show up on their news feed.