Mark Zuckerberg: "This type of thing is only possible because of the social infrastructure that already exists"
Facebook has announced a partnership with Skype to add video chat to the social networking site.
The move is likely to be seen as a shot across the bow of Google, which recently launched a Facebook rival, Google+, also featuring video calling.
This is not the first time Facebook and Skype have teamed up - they already share some instant messaging tools.
Skype is in the process of being bought by Microsoft, which is a major shareholder in Facebook.
The new video-call service was launched by Facebook founder Mark Zuckerberg, who also revealed that the site now had more than 750 million users.
However, he said that the total number of active users was no longer a useful measure of the site's success.
Instead, the amount of sharing - of photographs, videos and web links - was a better indication of how people engaged with the site, explained Mr Zuckerberg.
