MySpace and Facebook are slowing down ... Really? What do you think? 2 interesting articles MySpace Clips Facebook In January, But Both Slowing http://www.alleyinsider.com/2008/2/myspace_has_a_better_month_than_facebook__but_both_slowing Cory Doctorow: Social Pariahs Will End Facebook http://blog.wired.com/business/2007/11/cory-doctorow-s.html Do you remember Friendster?
Increase in number of users could be the reason, I am not aware what step they're going to take to solve this problem.
I think it could be just another trend, social networking is useful up to a certain extent but I cant see it replacing human to human interactions.