The new nameless-feature algorithmically determines which tweets are important to you (based on who you follow and engage with) and moves them to the top of your timeline when you open the app or launch the site. The featured updates will be presented in reverse chronological order in case you were worried Twitter was turning into Facebook. Twitter is hoping this will keep you from missing important updates. Michelle Haq, Twitter timeline project manager told Engadget, "we realized there's a ton of great content on Twitter and it's not always easy to find that great content."
While this seems like a super-charged version of While You Were Away, Haq insists that they are two different features. "While You Were Away only shows when you been away for a very long time," Haq told Engadget. While this new timeline feature could potentially be there whenever you open the app or load the site dependent on how many people you follow and how often they tweet. After a quick refresh, the timeline goes back to showing all your full timeline in reverse chronological order.