Online shoppers displayed a "new comfort level" with advanced interactive online advertising this holiday season, according to new monitoring data.

Digital marketing services firm Eyeblaster reported today that rich media advertising is succeeding in targeting retail consumers and inviting interaction "as never before".

The study shows a major shift among online retail advertisers toward user-expandable advertising, which showed a 35 per cent increase in viewing duration compared with the same period in 2006.

Expansion duration, i.e. the time a consumer spends interacting with an ad in its expanded state, provides a direct measurement of consumer interest and perceived relevance of ad content, according to Eyeblaster.

"Campaigns running during high-volume periods, such as the holiday season, must pay extra attention to ensuring a high-quality and consistent brand experience," said Brad Rinkin, vice president of marketing at Akamai Technologies.