Seeing tweets from people you don't follow, and that aren't retweets? That's no longer an experiment, but a feature, Twitter says. A new change to the service is surfacing tweets from users people aren't following, something Twitter suggests will make things "more relevant and interesting." The company explains it like this on its support page (emphasis mine):
Additionally, when we identify a Tweet, an account to follow, or other content that's popular or relevant, we may add it to your timeline. This means you will sometimes see Tweets from accounts you don't follow. We select each Tweet using a variety of signals, including how popular it is and how people in your network are interacting with it. Our goal is to make your home timeline even more relevant and interesting.
Twitter began rolling this behavior out to users late last week, though it was believed to be an experiment that only affected some users, and potentially for a limited time. It was also unclear exactly what exactly Twitter was relying on to surface certain tweets to particular users. That exact science is still kind of a mystery, so let's just call it an algorithm.
This alters the way Twitter's worked for years
The policy change, which was spotted by Quartz, represents a marked change in how the Twitter timeline works. The original idea has been for it to solely show users posts from people they follow, and the retweets their followers decide to share. Things like sponsored tweets have muddled that, but those items have been clearly marked. By comparison, this change means potential noise and intrusion for users who have carefully pruned their lists, while Twitter clearly views it as a way to help surface content to people. That's already ruffled some feathers among users, who have complained about seeing things they don't want to see in their timelines.
The change is not unlike what Facebook did with its News Feed, going from showing you things from just your friends, to surfacing posts from friends of friends and promoted posts. The key difference is that Twitter's core service has been a chronological feed that's interrupted mainly by retweets, whereas Facebook's News Feed is supposed to surface things based on your activity and past history (or if it's doing a psychological experiment on its users).
Twitter declined to comment on the change.