"Ms. Sandberg's departure is a blow to Google, where she was a well-regarded executive... Mr. Zuckerberg is 23 and Ms. Sandberg is 38, but the age difference did not stand in the way of building a working relationship. The pair met at a Christmas party last December... Mr. Zuckerberg and Ms. Sandberg then spent time discussing Facebook's future at the World Economic Forum in Davos, Switzerland, in January and over a series of dinners at Ms. Sandberg's home in Atherton, Calif." [NYT]