Facebook Ceases Support for IE7
"It appears that Facebook has stopped supporting Microsoft’s Internet Explorer 7 browser, according to our friends at The Sociable. While this isn’t surprising since the browser is five years old, it is a bit of a hack for those who would rather not use Facebook’s Timeline feature to browse the site."
So they haven't quite dropped support yet. Still a good case study to present to stubborn bosses/clients who insist on IE7 support.