14 DAY TRIAL // There's no doubt in anyone's mind that Facebook is the biggest social network out there and the gap between its 'competitors' is especially noticeable in the US.
That's not to say that there aren't any other social sites out there, Nielsen put together a top of the most visited such sites in the US.
It's perhaps a bit strange that analytics companies still group blogging sites and social networks, but it wouldn't be much of a top 10 if they didn't.
Isolating the social networks, Facebook had almost 138 million unique visitors per month in 2011, up to October. Its closest competitors, Twitter, only had 23.5 million unique visitors, quite a gap.
It gets worse, MySpace had about 18 million unique visitors, but it's been on a downward trend, so the number should be smaller later in the year. LinkedIn had about 17 million visitors each month and Google+ only managed to get eight million visitors on average.
Google+ is a special case, since it was only launched in June and only to a limited number of users. Nielsen's numbers go from January to October, so Google+'s average number of visitors is artificially low.
Google+ should be seeing a significantly larger number of unique visitors, at least based on the latest registered users estimates, which peg the social network at about 65 million users at this point.
Registered users is one thing, active users is another, but many of those 65 million are from the US and almost a quarter of them signed up in the last month alone.
So, by this time, Google+ should be closing in on LinkedIn and MySpace and may have even overtaken them. However, it's probably not as big as Twitter yet.
Twitter has over 200 million registered users, 100 million of which visit the site each month. But it has a much more spread out audience geographically, explaining the small US number.