Katy Perry joins Mark Zuckerberg's social network

http://www.youtube.com/watch?v=gWuO46fQiHkendofvid[starttext]g's social network Facebook friends: Katy Perry poses with Facebook founder Mark Zuckerberg at the offices today in Palo AltoKaty Perry has a new Facebook friend.The singer cosied up to the website's founder Mark Zuckerberg at the company's Palo Alto offices in California today.The social networking enthusiast uploaded a picture of the