Change.org launched in 2007 as a social networking site for non-profits. Today, the site looks quite a bit different and has morphed into a petition platform that wants to empower activists around the world through what it calls “people-powered campaigns.” While the site only grew rather slowly in its early years, it’s on a tear now. According to Change.org’s own data, the site just passed 10 million users and is now growing by 2 million members per month. That’s quite a difference from last October, when the site was only growing by about 300,000 members per month. This makes Change.org the fastest-growing site of its kind.

After a few pivots (it was once a blog network, too), the site now almost exclusively focuses on petitions. As Change.org’s CEO Ben Rattray told me earlier this morning, the rise of social media helped propel people’s impression of what petitions can achieve forward. Not too long ago, petitions still had somewhat of a bad reputation and most people simply assumed that they didn’t work. In Rattray’s view, however, the rise of social media has made it clear to more people now that they can put pressure on their governments and large corporations by banding together. At the same time, of course, Change.org also uses social media tools like Twitter and Facebook to spread the word about its petitions.

Some of the site’s most notable recent campaigns include petitions to get Verizon to drop its highly unpopular online payment fee, a campaign against Bank of America’s $5 debit card fee, and a petition to fight the “corrective” rape of lesbians in South Africa, which 171,000 people from 175 countries signed last year and which forced the South African Parliament to establish a task force to end this practice. Even more recently, though, a petition with over 2.2 million signatures demanding an arrest in the Trayvon Martin case broke virtually all of the site’s records.