Facebook, the internet social networking site founded by Mark Zuckerberg, has appointed 38 year old Sheryl Sandberg as its Chief Operations Officer. Sandberg, a Harvard graduate, was previously Vice President of Global Online Sales and Operations at Google.

Facebook, founded in February 2004, has grown by leaps and bounds and the appointment of Ms. Sandberg replaces the void left by Owen Van Natta, who was made Chief Revenue Officer.

Ms. Sandberg will report directly to Mark Zuckerberg, thereby making her a virtual No.2 in the management.

She was the youngest in Fortune magazine’s 2007 list of ”500 most powerful women ”.

Sandberg’s departure rocked Google shares, which fell by as much as 4.6 %. Sandberg had joined the search engine giant in 2001, and was chiefly responsible for the success of its online advertising business, Adwords.

In other news, Forbes’ annual list says that Mark Zuckerberg is the youngest self made billionaire in history. Zuckerberg has been valued at  $ 1.5 billion by the magazine, which has conservatively estimated Facebook to be worth $5 billion. Zuckerberg has a 30 % stake in Facebook, and is 785th on the Forbes list. Sergey Brin and Larry Page, co founders of Google, are 32nd and 33rd on the same list.