of facebook, sheryl sandberg. they are the driving force behind one of the most exciting and powerful companies in the digital world with 800 million users and counting. you know what excites me about facebook... >> well, you canoin. we have many openings. >> rose: (laughs) i do. it is this point. it is the notion that very soon you're going to reach a billion. when will that happen? >> i don't know. >> rose: when do you think it will happen? >> well, everyday we're closer. >> it's now 800 plus and counting. >> yes. >> rose: it is going to be in 20? >> i think if we do well it might be later next year, yeah. >> rose: will that be a huge celebration? >> yeah. i think... i think it's going to be something we're going to be really proud of. >> rose: zuckerberg and sandberg for the hour. captioning sponsored by rose communications from our studios in new york city, this is charlie rose. >> rose: mark zuckerberg, only 27 and worth an estimated $17 billion started facebook as a harvard frhman in 2004. he, like bill gate

sheryl sandberg married and the mother of two came from a different place. she was a hugely successful google executive after servings achieve of staff for the secretary of treasury. she is a graduate of harvard university and harvard business sool. she was recently named among the 50 most powerful women in business by "fortune" magazine. mark recruited her from google in 2008. >> i was a google at the time. >> rose: so did you think at that moment, did you think hmm, maybe this is somethin-- >> a few people who i really respect h pointed sheryl out as someone who could be a really partner for me at facebook. but at the time, i mean, i was just really interested because i had a lot of respect looking at what you built at google and wanting to get a sense for some of the lessons that you learned and just for you, even if we didn't work gether, how could i apply some of those things to facebook. but i mean after that i think, i went away over the new year's eak and i got back. and i thought i nt to spend more time learning from sheryl. >> but i think the reaso

rose: also thisvening a look ahead at an explus-- exclusive interview with mark zuckerberg and sheryl sandberg of facebook. >> if you look past f the 7 years, the story of social networking has really been go about getting these 800 million connected so they can stay in touch with all these people who thecare about and getting them signed up for facebook and all that. but if you look forward for the next five years, i think that the story that people are going to rememr five years from now isn't how this one site was built t was how every single service that you use is to you going to be better with your friends because they can tap into your friends. so whether it's music services, and we just announced this new product, a little more than a month ago. and since then, some of the music services that are out there, spotifi has grown from a little more than 3 million users with face bok to now more than 7 million users with facebook. >> rose: we conclude with joan didion's memoir of her late daughter, it is called blue knight. >> it is not a narrative. the only book i have really written that w