"Measurement is a a real problem. ... How do you prove to a traditional client that advertising online is worthwhile?" said Adam Gerber, director of media strategy for the Digital Edge.
Marketers are increasingly demanding quantifiable results from interactive advertising, Mr. Gerber said, and the industry must make the Internet an accountable medium.
The problem is so pronounced that some marketers are shying away from all but the most experimental interactive programs.
Aside from measurement, panelists at today's event said consumer expectations of the Internet are quite high, while their tolerance for intrusive pop-up and pop-under ads, bugs skittering across their computer screens and scrolling banners is, not surprising, low.
"The consumer will not tolerate intrusiveness," said Jim McDowell, VP-marketing, BMW of North America, which introduced a successful Internet program of short films earlier this year at bmwfilms.com.
John Messina, director of agency relations for AOL Time Warner's America Online, claimed AOL doesn't do intrusive advertising -- "the subscriber is sacrosanct within our walled garden."
Of course that excludes heavy promotion for Harry Potter and the Sorcerer's Stone, from the media giant's Warner Bros. studio.