Amazon, Federated Media also see big gains in audience by year's end, comScore Media Metrix reports.
Inside the Beltway, special interests see their influence and power erode, tweet by tweet.
Also on Wednesday, Wikipedia and Redditt will go dark to protest anti-piracy legislation.
Social answering service gets a big lift in user sign-ups, while marketers ponder the site's advertising potential.
Whatever your opinion on the subject of social, one has to admit it's causing a communication revolution.
The companies that leave a burning impression on their prospects will be the ones who will be the leaders in this next period of growth.

June 6, 2012
1:00pm ET / 10:00am PT