Facebook is the dominant social network around the world according to the latest analysis by Vincenzo Cosenza, director at Digital PR in Rome, Italy, who has been tracking its growth over the past eighteen months or so. Even a cursory glance at the map above makes it clear when you see how much of that map is now coloured Facebook blue.

Superlatives abound when it comes to talk about Facebook, notably the 500 million members worldwide milestone the social network passed this summer. And there’s often talk about how those numbers pale into relative insignificance when compared to social networks like China’s QQ instant messaging network which says it has more than 500 million members, or social networking site RenRen with its 100+ million membership. It’s worth noting that such networks operate in a country which has blocked Facebook and others, giving clear advantage to domestic offerings. (As an aside, RenRen is planning an initial public offering in the US early next year.)

Notable changes in the map colours since Cosenza’s last analysis in June show Facebook supplanting Iwiw in Hungary, Nasza-Klasa in Poland, Hi5 in Mongolia, and Orkut (Google) in Paraguay and India. Overall, says Cosenza, Facebook is now dominant market leader in 115 countries out of the 132 he tracks.

Cosenza also highlights what he sees happening right behind Facebook:

[…] If we take a look over Facebook’s shoulders we can see the rise of Twitter especially against MySpace (in Australia, Canada, Germany and Italy) and the slow but constant growth of LinkedIn (in Australia, Canada, UK). New entries since last June analysis highlighted in yellow.

(SNS = social networking site.) Clearly Facebook is king of the hill in just about every major market. Still, from a business point of view, don’t ignore domestic social networks with memberships still in the millions – which service you use to connect with customers and others doesn’t only depend on the numbers. As Procter and Gamble says, you need to be where your customers are, whether that’s Facebook or somewhere else.

Check Cosenza’s post for more information including a neat infographic comparing the development of social networks around the world in each six-monthly period since June 2009.

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