Facebook have made URL to setup the Video calling and you can easily install the software which is required to be have for a video chat with the friends, and you will see the new Video Chat button in the same chat video, as you click on the icon and chat will start and you would able to see your friend , but it could possible only when you have web cam, if you don't have web cam then you can use your cam enabled mobile as a web cam and establish a video chat with your friends.
Facebook video calling setup URL is http://www.facebook.com/videocalling, Login in Facebook Account and click on this URL and you should have web cam also then you will see the button of Get Started, after clicking on this button, you will see the new Icon of video chat button in the chat window as you click on this, you will be prompted to install the Plugin of Facebook Video Chat, install the installer and after all this you could make call to any friend from the chat window and could have video conversation.
Facebook Video Setup FAQ at http://www.facebook.com/help/?page=177940565599960
