Facebook today announced that users will be able to group pages and public figures into “interest lists” so that they can filter their News Feed by topic.

We spotted this feature last week and suggested it would be another challenge to Twitter, which offers a similar list capability. Facebook users have long been able to create lists to organize their friends, but there hasn’t been an option to group pages until today.

Facebook says users will see an “Add Interests” link in their left-hand bookmarks in coming weeks. From there, users can subscribe to lists from other users or create their own. Interest lists can include pages, subscriptions and friends. The top stories from each interest will appear in News Feed with a link to read more posts.

When users view a list, it appears as a filtered version of News Feed, similar to how people can view individual friend lists. The difference is that users can share and subscribe to each other’s interest lists if they make them available to friends or the public. Users can also create lists that only they can see. There are additional controls for users to select what type of stories to include or exclude in the feed. For example, you can select to see only photos from a page or only music and videos from a public figure.

As we noted last week, Facebook has been aggressively pursuing the “interest graph” — the relationship between people and topics. Many have pointed to Twitter as beating Facebook in this area, but with the subscribe feature and now interest lists, the social network is catching up.

It’s too early to tell, but interest lists could change how people view and interact with stories from brand pages. If users see posts among others on the same topic, they might be more engaged than when they see these posts among others from friends and unrelated pages. It also means users don’t have to Like pages in order to see updates from them. This raises questions about how ads will be targeted depending whether a user Likes a page or subscribes to it.

Still, interest lists are likely to be a power user feature. In 2010, Facebook said only 5 percent of users created friend lists, which launched in 2007. With the ability to subscribe to interest lists created by others, however, more users might adopt the feature. The company is also likely to promote the feature heavily in sidebars and other areas, as it has done with “People to subscribe to.”

[Update 3/8/12 11:14 a.m. PT - Facebook is already highlighting interest lists created by public figures. For example "Cast of Glee" created by Ryan Seacrest, "Washington Post Staff" created by journalist Mark Luckie and "NFL Players" by ESPN Adam Schefter.]

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