"nearly 50%" of US users visit social networking sites...sort of

According to Nielsen/NetRatings, social networking sites attracted 45% of active internet users in America in April. (see article in TechWeb)

MySpace: 38.4 million unique users
Blogger: 18.5 million unique users
Classmates: 12.9 million unique users
YouTube: 12.5 million unique users
MSN Groups: 10.6 million unique users

That's 92.9 million unique users visiting the same sites but let's not get overly excited about the numbers - I reckon that a lot of those users are the same people, visiting a number of "social networking" sites.

Blogger shouldn't be on this list at all - it's a blogging platform, not a social networking site. In fact, it's hardly a website at all - you only visit to log in to the tool, not to social network. Subtract Bloggers 18.5 million users from the list please.

I'm also of two minds about the inclusion of YouTube. To me it's a publishing platform for videos but I suppose there are some who would argue it's a community. I'm going to subtract their 12.million from the list anyway.

So what are we left with? 61.9 million unique users, many of them unique to each site on the list but visiting more than one site each. (Of course, the two sites I substracted from the list will be replaced by other sites but those sites will be worth less than 10 million unique users each.) So there were about 80 million unique users visiting social networking sites in the US and lots of those users probably visited more than one of them - it's not quite the "almost half!!" that's being reported.