NEW YORK (AP) — Amid chatter of "Facebook fatigue," real or imagined, the world's biggest social networking company is getting ready to unveil a new version of News Feed, the flow of status updates, photos and advertisements its users see on the site.

Facebook Inc. is hosting an event at its Menlo Park, Calif., headquarters on Thursday to show off "a new look for News Feed." The company offered no other details on what the changes will be in an invitation sent to journalists and bloggers. It will be Facebook's second staged event at its headquarters since the company's May initial public offering. The company unveiled a search feature at the first one in January.

If past site changes are any indication, the News Feed tweaks may take some getting used to and will likely lead to user grumbles. Facebook users often complain about changes to the site, whether it's cosmetic tweaks or the overhaul of privacy settings.

Gartner analyst Brian Blau says one change he'd like to see from Facebook as a user is the ability to control how much he's seeing from the businesses and other non-friend accounts he follows. Currently users can only tweak how much they see from their friends, not from businesses they follow.

"We have a 'like' but there is no degree of 'like,' it's binary," he says. "I need a 'like plus' or even a 'like minus.'"

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 some 61 percent of Facebook users had taken a hiatus for reasons that range from boredom to too much irrelevant information to Lent.

Overall, though, 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.

"For example, we believe that some of our users have reduced their engagement with Facebook in favor of increased engagement with other products and services such as Instagram," the company said last month in the "risk factors" of its annual 10-K filing. "In the event that our users increasingly engage with other products and services, we may experience a decline in user engagement and our business could be harmed."

Facebook owns Instagram, but so far it has not shown any ads on it.