Comscore Releases September 2011 U.S. Online Video Rankings

Online Video Ads Now Reach 50 Percent of Total U.S. Population Each Month

RESTON, VA, October 21, 2011 – Comscore, Inc. (NASDAQ: SCOR), a leader in measuring the digital world, today released data from the Comscore Video Metrix service showing that 182 million U.S. Internet users watched online video content in September for an average of 19.5 hours per viewer. The total U.S. Internet audience engaged in 39.8 billion video views.

Top 10 Video Content Properties by Unique Viewers

Google Sites, driven primarily by video viewing at YouTube.com, ranked as the top online video content property in September with 161 million unique viewers, while VEVO ranked second with 57.3 million. Microsoft Sites climbed to the #3 position with 54 million viewers, followed by Viacom Digital with 53.4 million and Facebook.com with 49.9 million. Nearly 40 billion videos views occurred during the month, with Google Sites generating the highest number at 18.6 billion. The average viewer watched a record 19.5 hours of online video content, with Google Sites (6.3 hours) also demonstrating the highest engagement.

*A video is defined as any streamed segment of audiovisual content, (both progressive downloads and live streams).
For long-form, segmented content, (e.g. television episodes with ad pods in the middle) each segment of the content
is counted as a distinct video stream.

Top 10 Video Ad Properties by Video Ads Viewed

Americans viewed more than 6.8 billion video ads in September, with Hulu generating the highest number of video ad impressions at more than 1 billion. Tremor Video ranked second overall (and highest among video ad exchanges/networks) with 811 million ad views, followed by Adap.tv (803 million) and BrightRoll Video Network (665 million). Time spent watching video ads totaled more than 2.9 billion minutes during the month, with Adap.tv delivering the highest duration of video ads at 450 million minutes. Video ads reached 50 percent of the total U.S. population an average of 45.3 times during the month. Hulu delivered the highest frequency of video ads to its viewers with an average of 38.2.

*Video ads include streaming-video advertising only and do not include other types of
video monetization, such as overlays, branded players, matching banner ads,
homepage ads, etc.
**Indicates video ad network
†Indicates video ad exchange

Top 10 YouTube Partner Channels by Unique Viewers

September marks the second month of official rankings for Comscore YouTube Partner Reporting within the Video Metrix offering, providing a comparison of viewership across thousands of YouTube partners and their channels. The data revealed that video music channels VEVO (57.3 million viewers) and Warner Music (28.8 million viewers) maintained the top two positions. Gaming channel Machinima ranked third with 17 million viewers, followed by Maker Studios with 9 million, Demand Media with 6.8 million and Revision3 with 5.4 million. Within the top 10 partners, Machinima demonstrated the highest engagement with 61.9 minutes per viewer on average, while accounting for the second most videos viewed (249 million) after VEVO.

*YouTube Partner Reporting based on online video content viewing and does not include
claimed user-generated content

Other notable findings from September 2011 include:

• 85.3 percent of the U.S. Internet audience viewed online video.
• The duration of the average online content video was 5.3 minutes, while the average online video ad was 0.4 minutes.
• Video ads accounted for 14.7 percent of all videos viewed and 1.4 percent of all minutes spent viewing video online.

About Comscore
Comscore, Inc. (NASDAQ: SCOR) is a global leader in measuring the digital world and preferred source of digital business analytics. For more information, please visit www.comscore.com/companyinfo.

Contact:
Adam Lella
Comscore, Inc.
+1 (312) 775-6474
press@comscore.com