A new study called The Face of the Web finds that the United States ranks fifth when it comes to the percentage of adults who have visited a social networking website.

South Korea, Brazil, China, and Mexico all have a higher percentage of adults who have visited a social networking site at least once within a thirty-day period. And when you consider the massive populations of Brazil and China, that’s a lot of people getting their profiling and friending and all the rest of it on.

And while MySpace may still be dominant in the US, other parts of the world have different tastes. Facebook is with MySpace in the UK, with Bebo making a strong going of it as well. Friendster, exiled after MySpace usurped its power several years ago, still reigns supreme in parts of Southeast Asia. And Cyworld, kind of a social MMO (massive multiplayer online game), is the darling of South Korea.

that Brian Cruikshank, an exec at Ipsos, contends that it’s possible that the massive popularity of social networking websites may have an affect “on other online and offline entertainment behaviors that ultimately compete for a share of the consumer’s disposable time.”

This line of thinking ties into a conversation that has been ongoing since late last week on and a number of other sites. It kicked off when Robert Scoble asserted that top bloggers are losing traffic because of the popularity of sites such as Facebook.

My counter-argument ran thus:

In my view the blogosphere and social networking worlds have very different cultures and people who fill them up. So it’s not a zero sum game i.e. the popularity of Facebook (and hasn’t MySpace had a billion registered users for several years already? How did Facebook reinvent the wheel?) does in no way deflate the popularity of the blogosphere or any “A List” bloggers in the process.

Now, if you want to argue that some bloggers are losing audience due to some notion of “more choice than ever before” (more quality bloggers, more web communities, more high quality content, etc. etc.) that’s something I’d be interested in hearing out.

That said, there’s no doubt that online social networking is having a massive impact on how people around the world are communicating. And hundreds of start-ups are trying to cash in on various niches of the social networking world – from horses to moms to honoring the deceased to college sports and everything in between.