Memes on Facebook

http://www.slate.com/id/2211068

"A survey of about 3,000 people who were tagged in a "25 Random Things About Me" note on Facebook found that memes spread through social networks in a remarkably similar way as diseases do. A biologist who looked at the data says that "'25 Things' authors can be seen as 'contagious' under what's known as a 'susceptible-infected-recovered' model for the spread of disease," with a propagation factor of 0.27 in this case. But like an infection, the whole thing died out as quickly as it exploded once the number of 'victims' — people who were willing to write 25 things about themselves — was depleted."