Yep. According to Mr Zuckerberg,

As of this morning, 500 million people all around the world are actively using Facebook to stay connected with their friends and the people around them.

Yay! And some of those 500 million may one day come to regret some aspects of their social networking.

According to a recent survey by Microsoft, 75 percent of U.S. recruiters and human-resource professionals report that their companies require them to do online research about candidates, and many use a range of sites when scrutinizing applicants — including search engines, social-networking sites, photo- and video-sharing sites, personal Web sites and blogs, Twitter and online-gaming sites. Seventy percent of U.S. recruiters report that they have rejected candidates because of information found online, like photos and discussion-board conversations and membership in controversial groups.