It’s been coming for what seems forever now – Facebook finally overtook MySpace. ComScore reports that the milestone was reached in May, with Facebook growing to 70.278 million unique visitors while MySpace fell to 70.255 million. Facebook gained 2.8 million unique U.S. visitors last month while MySpace lost 500,000. If Facebook integrates a good music service, MySpace will be done. Year-over-year, Facebook grew 97 percent from 2008 while the MySpace audience shrunk 5 percent. In the same period, Twitter has grown 2700, though earlier this month Compete reported that Twitter adoption had flatlined in May, stopping its astounding 2009 growth.

Twitter grew from 6 million unique visitors in January to 19 million in April. Between April and May, however, the microblogging site grew by less than 300,000 unique visits, an increase of less than two percent.

iMedia believes that Twitter will be obsolete in a year, basing the argument on Twitter’s 30 percent retention rate and noting the speed with which social networks get replaced: the Friendster-MySpace-Facebook/Twitter evolutionary cycle is only seven years old.

Each successive site has been more popular than the last, and the more interactive socnets become, the more of our time they will likely consume. At the expense of other things, some fear.

The Annenberg Center for the Digital Future at the University of Southern California is attempting to correlate increased time on social networks with decreased family time, noting that as the first trends up, the latter falls down.

Twenty-eight percent of Americans interviewed by Annenberg in 2008 spent less time with their families than in the previous year, up from 11 percent of people who replied similarly in 2006.

Concerns over children's internet consumption is also growing. In 2000, only 11 percent of survey respondents said that family members under 18 were spending too much time online. In 2008, that number was 28 percent.

"It's not like television, where you can sit around with your family and watch," said Annenberg’s Michael Gilbert.

But it's sort of getting there.

By Mark Alvarez