In response to word that Yahoo and Google want to use their email services to compete with social networks, Fred Wilson tried to compare the "social graphs" of popular Web email services against popular social networks, but he couldn't get it all on one chart. Here's our chart, courtesy of ComScore. It shows the outlook for Google and Yahoo is good, if they manage to turn their email user base into a workable social graph, whatever that means.

You've seen our charts which show how email's dominance is fading. Yesterday, Slate came to the same conclusion, citing a 2005 Pew study, which reports that nearly half of Web-using teenagers prefer instant messaging to email. Slate also dug up last year's news from ComScore's that teen email use was down 8 percent. The cause?