Yesterday the Online Publishers Association announced that 37 members, including The New York Times, Forbes, ESPN, CNN and MSNBC.com, are planning to start running the new, larger ad units the organization introduced last March.

With brands like Bank of America and Mercedes-Benz that reach about 68% of the total US internet audience, the formats have a strong launchpad.

The three ad units are named and sized as follows:

• The Fixed Panel (336×700) - remains in view as a user scrolls up or down the page
• The XXL Box (468×648), the extra wide side-of-page ad that expands to 936 x 648 and includes page-turn and video capability
• The Pushdown (970×418), which opens big to display the ad and then after seven seconds rolls up to the top of the page (collapsing to 970 x 66).

The real motivation was to provide marketers and agencies with the opportunity to deliver a branded experience directly on the pages of these very rich content sites, OPA President Pam Horan was quoted as saying.

OPA recommends that the frequency of the pushdown ad be capped at once per day per page in order to stay close to consumers.

A recent poll found that over one-third of Americans (37%) say TV ads are most helpful to them in making a purchase decision, while nearly half say they ignore internet banner ads.

Last week, it was reported that online consumers exposed to display advertising are 50% more engaged with advertisers' brands and spend 10% more money online.