Following someone’s posts can be a distracting business. You’re interested in one coworker’s posts, and suddenly your feed is overrun with posts from everyone else who is, too. In the Winter ’16 release, all new Salesforce orgs limited the What I Follow feed to who you actually follow—no more interlopers! Now we’re sharing this goodness with older orgs. (We don’t enable the updated follow model for orgs that have opted out of auto-enabling.) Post an update to a coworker’s profile. Now the only people who see your post are the coworker, the people who follow you, and the people you @mention. This feature is available on all platforms.
If you opted out of auto-enabling new features in your org, contact Salesforce to get this update.