Facebook is close to 700 million members mark. It continuos to be the top social network establishing its leadership in many countries. Brazil & India, where Orkut was leading, facebook is gaining popularity. Here is a chart of top social networks across the globe. There are many country specific sites which are popular in regions like Maktoob in Arab, QQ in China, Zing in vietnam & others. Twitter & Youtube are also gaining popularity & membership of twitter is also increasing.
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