Facebook (Nasdaq: FB), operator of the world’s largest social network, is testing a new feature that lets users in the U.S. pay to promote their own posts on the website.

The new tool, which was introduced in more than 20 countries before its start Wednesday in the U.S., also gives users the ability to track how many friends notice the post, Facebook said on its website. The initial test price will be $7 for promoting a post, and other price points will be tried out in the future, the company said in an e-mailed statement.

“When you promote a post – whether it’s wedding photos, a garage sale, or big news – you bump it higher in news feed so your friends and subscribers are more likely to notice it,” Facebook said in a statement on its website.

Facebook, which already lets companies pay to promote posts, is looking for ways to generate revenue outside of its core advertising business as investors clamor for more monetization of its more than 950 million users. Last month the company introduced a gift-giving feature for users to buy and send items to their friends to mark birthdays and other events.

On Thursday morning, Facebook Chief Executive Officer Mark Zuckerberg shared news that he really liked.

Facebook has topped 1 billion users.

“This morning, there are more than one billion people using Facebook actively each month,” Zuckerberg wrote to people who “like” the social media giant.

“If you’re reading this: thank you for giving me and my little team the honor of serving you,” he said in updating his own Facebook status.

“Helping a billion people connect is amazing, humbling and by far the thing I am most proud of in my life.

“I am committed to working every day to make Facebook better for you, and hopefully together one day we will be able to connect the rest of the world too.”

Zuckerberg acknowledged that the company is going through a bit of a rough patch following its rocky initial public offering.
The Menlo Park, Calif.-based company has had a difficult time of late. There were trading glitches the day it went public in May and concerns since then about its revenue potential. It’s also facing lawsuits from disgruntled shareholders.

Zuckerberg said in a “Today” show interview Thursday that “we’re in a tough cycle now and that doesn’t help morale, but people are focused on what they’re building.”

Last month, Zuckerberg gave his first interview since Facebook’s shaky IPO, and since that time he’s been working hard to boost confidence among investors and the public.

Zuckerberg told Matt Lauer during the “Today” interview that Facebook’s future is about mobile, an area it’s been criticized for not capitalizing on quickly enough.

The 28-year-old executive also continued to reassure that he is the right person to lead Facebook, as some on Wall Street have questioned whether he has the ability to lead a large public company.

“I take this responsibility very seriously,” he said.

(The AP and Bloomberg contributed to this report.)