Comscore Selected as the Most Preferred Online Audience Measurement Service by Over 50 Percent of Respondents in William Blair Survey

Lead Over Nearest Competitor Increases to 25 Percentage Points

RESTON, VA, January 26, 2009 – Comscore, Inc. (NASDAQ: SCOR), a leader in measuring the digital world, today announced that it was rated as the preferred audience measurement service by 50.4 percent of respondents to the William Blair & Company 6th semiannual survey of the members of the Chicago Interactive Marketing Association (CIMA). The results for Comscore extends its lead versus its nearest competitor to 25 share points and represent a 5-percentage point gain from the mid-2008 survey.

William Blair noted that “our proprietary tracking indicates that Comscore continues to extend its leadership position in the digital marketing intelligence industry, with data from our semiannual CIMA survey conducted in December 2008 indicating Comscore was preferred over its nearest competitor, Nielsen Online, by a 25-share point spread, which is up from a 20-share point lead in the last survey.”

Dr. Magid Abraham, Comscore President and Chief Executive Officer commented: “Comscore’s expanded leadership position is a testament to the outstanding efforts of the entire Comscore team, which has worked tirelessly to provide the global Internet industry with a powerful and compelling suite of products that measure the digital world. Our commitment to innovation, continued improvement, and meeting the constant challenges of evolving digital media is only strengthened by this important market validation.”

To conduct the survey, William Blair partnered with CIMA, which boasts a membership base of more than 800 organizations, covering publishers, advertisers and advertising agencies. Approximately 150 members of CIMA participated in the survey. William Blair commented that CIMA is: “One of the world’s most active Internet marketing associations and the advertisers represented by this community provide an ideal interactive market barometer, as they are more likely to represent established marketers that control some of the largest online ad budgets in the world.”

About Comscore
Comscore, Inc. (NASDAQ: SCOR) is a global leader in measuring the digital world. For more information, please visit

Bill Daddi
Daddi Brand Communications