The feature lets users organize tweets by other users to show what they consider the most important tweets about a topic or event.
The feature is similar to Storify's embeddable stories, though Storify's offering lets users bring in content from Twitter, Facebook, YouTube, Flickr, Instagram and more.
Twitter gave a few select partners early access to the feature to demonstrate the kinds of things people can do with it.
Carson Daly, host of NBC's "The Voice," created a custom timeline of hand-picked tweets about the show that'll serve as a companion for those watching tonight's episode. The Guardian is using the feature to run a live Q&A session between their readers and reporters on the topic of NSA revelations.
Twitter will also be offer an interface that will let programmers access tweets from the back-end and create timelines based on custom logic.
Politico used this interface to create a "Tweet Hub" for energy policy news. The page has three custom timelines that automatically aggregate tweets from noted energy journalists, organizations, and politicians, respectively. Together, the page gives a good idea of what's happening in the energy policy discussion at any given time.
TweetDeck users will be the first to have access to the new feature - those interested in curating tweets can check out the tutorial Twitter posted on the TweetDeck blog.