Microsoft and Facebook launched Docs.com a online documents sharing site witch is powered by Facebook login so it mean this is going to one of the big site, because Facebook is one of the best social media site and now Facebook user can share there document to all friends.
Now you can upload word, excel and power point document to Docs.com using Facebook id witch mean all your friends can view this document, there is also option for private data witch mean that document want available for everyone, only you can see that document.
via:docblog