Here is an infographic that tracks key statistics of major social networks.
It is amazing to see how Facebook is far, really far ahead with 310 million unique visitors per day and 640 million registered members.
Regarding the number of daily visitors, Orkut comes in 2nd place with “only” 51 million visitors a day. StumbleUpon is 4th with 27 million, Twitter 5th with 22 million (and Flickr: 11 million, Linkedin and Badoo: 8 million). Now regarding the number of registered users Twitter has a very nice 2nd place with 200 million users.
The figures in the Social Media Landscape are still impressive even though many are beginning to say that their Best Time already has been reached. Moreover we can see the horizontal progression line of Facebook members in 2011.
Too bad the creative does not include figures for Google + (which was around 25 million visitors per day according to Comscore early August).