Sara Lacy of BusinessWeek interviews one of the tech industry's most intriguing story-lines over the last two years is the incredible growth of Facebook from college networking tool to global giant. Mark Zuckerberg has emerged as one of the brightest young minds in the booming social media industry. As Facebook continues to launch new innovations and expand functionality with Facebook Platform, the number of users on the site continues to soar — more than 60 million at last count.