Ars Technica asked Is Facebook “broken on purpose” to sell promoted posts?
TechCrunch rebutted this: Killing Rumors With Facts: No, Facebook Didn’t Decrease Page Feed Reach To Sell More Promoted Posts
"Facebook’s news feed ranking algorithm (widely known as EdgeRank) chooses between hundreds or thousands of pieces of content each day to show the few dozen most relevant stories in each person’s news feed. Facebook told me in February that the average Page reaches 16 percent of its fans with each post. That’s because some fans aren’t online when the post is published, a specific post hasn’t gotten much engagement from the people Facebook already showed it to, and because if you don’t interact with that Page when you do see its posts, Facebook will only show you them every once in awhile."
"What should Pages do now that they know what happened? Focus on publishing high-quality content. Don’t post too often and don’t cram your marketing down people’s throats. Be entertaining and informative. Then follow your analytics closely, consider hiring experts that can help, and refine your strategy. If your Page’s reach decreased, I’m sorry. It doesn’t mean you’re a bad Page, business, or admin. You just need to work on finding relevant content to post and delivering it with a natural non-spammy tone."
Robert Scoble chipped in.
If you take all this at face value, the implication is that looking spammy (overposting?) is bad. Instead of getting people to Like your pages, you want them to be "friends" with you. Or you just say Facebook has jumped the shark and move on to Google+.