• by Erik Sass  @eriksass1, August 25, 2010

Evan Harrison is leaving his post as the president of Clear Channel Radio's online music and radio division, according to an internal memo from President and CEO John Hogan, which was circulated among employees on Wednesday. Harrison will leave the company at the end of the year to pursue other opportunities.

His departure comes after six years in positions of increasing responsibility, leading the digital operations of the nation's largest radio broadcaster. During his tenure, Harrison presided over an almost continuous expansion of CCR's digital content offerings via multiple platforms.

Shortly after jumping from AOL Radio to CCR in 2005, Harrison led a wide-ranging overhaul of Clear Channel Radio station Web sites to standardize delivery of digital content and advertising. His goal was to attract incremental spending increases from local and national advertisers. He also oversaw the large-scale implementation of video content and advertising across the Web sites.

More recently, he directed the creation of a new Web site, IHeartMusic.com, to serve as a central music and media hub drawing on content from Clear Channel stations across the nation, and erockster.com, a crowd-sourced audio service focused on new music genres.

Harrison also implemented upgrades including improved ad-serving capabilities, which allowed advertisers to "follow" consumers; more preference-mapping to refine content offerings for individual consumers; and a raft of new mobile apps for smartphones including the Apple iPhone, BlackBerry, and Android.

In his memo, Hogan highlighted Harrison's success during his tenure at CCR, including "iheartradio.com reaching 10 million unique person downloads this year. In addition, each month 25 to 30 million highly engaged individuals visit our digital properties, where we offer advertisers truly integrated campaigns that include on-air, online, mobile and talent endorsements."

Perhaps more to the point, large online audiences have translated into substantial advertising revenues for CCR -- a prize that has eluded some other big radio broadcast groups that ventured on to the Internet.

While the company is typically secretive about revenue data for specific divisions (an industry watcher familiar with the business estimated that the digital operation's revenues cleared $175 million in 2008.)