When Facebook unveiled a new suite of analytics tools last October, one of the biggest pieces of news was a number labeled Talking About This, which showed up on brands' pages right under the number of total Likes, where anybody could see it. A lot of social-media-expert head scratching ensued. "These metrics are so new that everybody is still trying to understand them," says Susan Etlinger, a social-media metrics analyst with Silicon Valley research firm Altimeter Group.

Talking About This tallies all the users interacting with any Facebook page in the previous seven days-;that part is simple enough. The question was, What could a company do with that information? At GoPro (read the February cover story of Inc. about GoPro) and other companies, the answer was, Turn it into a rate by looking at it as a percentage of the total number of Likes. It's a simple way to measure audience engagement-;in GoPro-speak, it's called a BARE (brand audience rate of engagement) score. Other companies simply call it rate of engagement.

As its Facebook audience grows, GoPro can monitor its BARE score to make sure the percentage of users interacting doesn't get diluted. And because the numbers that make up the BARE score are publicly posted, the company can easily see how its audience activity stacks up against the competition's. Even better, because BARE is expressed as a percentage and not a hard figure, you can easily compare Facebook engagement across pages with different audience sizes.

Etlinger agrees that the rate of engagement score is a useful benchmarking tool, but she cautions that ultimately companies will need to dig much deeper to understand what specific kinds of content fuel the interactions on their pages (this could be different for every company) and how those interactions can fuel business-;whether through revenue or brand awareness or even ideas for product innovation.

"It's important to have users sharing content, posting comments, and returning to the page multiple times," she says. "It's a virtuous circle. People share, they co-create, and it all feeds back into the top of top of the circle." Sound familiar? She just explained Nick Woodman's content spiral.