But Zuckerberg said at the press conference from his Menlo Park, Calif., headquarters that the News Feed is "one of the most important services" in Facebook. "How we are all sharing is changing, and the design of your News Feed needs to reflect this evolving change."
The new changes began rolling out on a limited basis Thursday and on mobile devices in the next few weeks.
The new News Feed will focus on three fundamental changes the way the News Feed tells stories, the ability for the user to make choices on what feeds he or she wants to read, and making sure that the desktop version and mobile version are consistent in their user interfaces.
Photos will be displayed more prominently and grouped better together in order to tell a story, said Facebook Director of Design Julie Zhuo.
The places users visit will be emphasized with maps, and multiple posts of the same story or video will come together into one posting for simpler browsing. News posts and trending topics will be aggregated for users to see which have become the most-talked-about items.
"Put them all together . . . and you get a richer, simpler, more beautiful News Feed, both on desktop Web and mobile focused on things you care about," Zhuo said.
News Feed also will have a switcher that allows the user to show only those posts from friends or public figures they follow.
With the changes, postings can be prioritized by all friends, close friends, most recent, or by categories such as music-related or photos. The switcher also knows which way users view the posts most and will make that the most readily accessible.
Finally, all of these changes and the overall interface will look the same across all platforms that use Facebook, including mobile phones, tablets and desktop computers. The rollout will be slow, to ensure that bugs are worked out before a wide release.
Facebook's user base is growing, especially on mobile devices. At last count it had 1.06 billion active monthly accounts. The number of people who access Facebook daily is also on the rise.
That said, even the company has acknowledged that some of its users, especially the younger ones, are migrating to substitutes, but so far this has not meant an overall decline in user numbers.
The event comes a month after a Pew study reported that many Facebook users take a break from the site for weeks at a time. The report, from the Pew Research Center's Internet and American Life Project, found that 61 percent of Facebook users had taken a hiatus for reasons that range from boredom to too much irrelevant information to Lent.
The pressures for Facebook are acute, given its still-anemic performance on Wall Street. It came out of the box in May with an extraordinarily high valuation of $38 a share, which slumped to half last fall and has remained for the most part under $30. In trading Thursday, the stock closed at $28.50 a share, up $1.13.
The Associated Press and The New York Times contributed to this story.
Users will be able to drill down into topic-specific news feeds for music, for photos, and another for the publications, celebrities or brands they follow
The images and links to articles are bigger, making it easier to see on mobile screens
Pictures will show up bigger in the new feed
The space for ads will be bigger