I've seen several recent articles noting the declining popularity of Facebook. This appears in large part due to what seems is the flaw with the company's ever expanding News Feed and the content that is being pushed through that pipeline.
To retain users and keep them from switching to other social media platforms Facebook has been slowly growing its social capabilities to keep up with competition. For instance, when Foursquare was making a splash with users, Facebook simply added similar features, allowing users to check-in at locations and share that information with Friends.
Now, having done this dance a number of times over the past few years, Facebook has created an over saturated New Feed which has in-part been responsible turning users onto alternative social apps.