After several months of testing, Facebook is officially rolling out a new Trending feature that, just like on Twitter, lets users see what hot topics are dominating conversation on the social platform. The new Trending column, which will appear to the right of users' News Feeds, groups the most popular topics in a list and also displays a convenient headline summary alongside so you know why it's important. Facebook isn't just culling data from across its massive global reach and giving you a pulse on what the world-at-large is talking about, it's customizing this Trending feed based on your interests and friends. So clicking on any of these topics will take you a relevant post from a friend or a sponsored Page. Don't tweak, though, if you don't see Trending when you log on to Facebook for the day, as the feature's being introduced in phases globally. It's also only for the desktop as of now, though Facebook is currently testing it for mobile.