As Madison Avenue prepares for this week's American Association of Advertising Agencies conference in Scottsdale, Ariz., it faces some of the most daunting challenges since the mid-20th century, when TV replaced radio as the mainstream medium, writes the New York Times. "The agencies that will succeed are the ones not frozen in the era of 30-second television commercials and can find the new ways to engage and connect with consumers," 4As chairman Anthony J. Hopp is quoted as saying.

This year, there are more speakers from smaller, creatively focused independent agencies, which are landing business from large advertisers such as Coca-Cola, General Motors and Unilever - a change that is among the most profound affecting Madison Avenue.

Another welcome development is the arrival of "a new generation of leadership" at bigger agencies "for whom 'new media' isn't 'new media,' it's 'media,'" according to Ron Berger, chief executive and chief creative officer for the New York and San Francisco offices of Euro RSCG Worldwide, part of Havas.

Organizers expect 390 people to attend the 4As conference - the highest number since 2000, when it attracted 450 people. Attendance is considered a measure of the ad economy's health.