In a New York Times article reporting on Forrester Research stats http://tinyurl.com/nlxdrn, the reporter writes, "Time waster or not, social media are a phenomemon that is now nearly impossible to ignore."
I agree, but would drop the 'nearly' from the comment. The Forrester stats show 50% of adults visiting social network sites at least monthly. In my world, the number is even higher. In a show-of-hands survey in my communication course that just started at SFSU, that number was 100%. The social sites are a mode of communication so popular that they seem to be replacing much of the phone communication I used when I was in college.
The other Forrester stats are also interesting. Percent of adults who read blogs is 39%, contribute to forums and discussion groups is 23%, review products or services 19%, listen to podcasts 16%, publish, maintain or update a blog 12%, use RSS feeds 9%, and contribute to article in a WIKI 5%.
The contributing content side of these stats are telling of a cultural communication shift. In my SFSU classroom, other than social networking, the number of students who contribute online is relatively low (10%). But it is the increase in contributing to this 'impossible to ignore' phenomenon that will have the greatest effect on change.