Twenty-seven large publishers are introducing three new types of online display ads today. The new formats are meant to reduce clutter while getting more directly into the reader’s face — in contrast to banner ads, which are often plastered across web pages but still ignored by readers.

Publishers are trying to make themselves more desirable to large advertisers — companies like Coke, Pizza Hut and Proctor & Gamble — who want to sell their mass-market products to the generic consumer. These brands aren’t looking so much for direct online purchases or other actions, like what Google search ads promise; rather they want to tell users to try, say, a new type of Coke at the grocery store.

The new formats are being launched just as more traditional banner ads are dropping in popularity. One reason is that advertisers have less to spend — and they know banners aren’t getting results — and another reason is that the web is continuing to expand, creating ever more inventory for these ads. In other words, there are both fewer buyers and more sellers of online ad space than in past years.

The publishers involved in this initiative, including national newspapers like The Wall Street Journal and USA Today, magazines like Forbes and Condé Nast and multimedia sites like MTV Networks and ESPN are hoping these new ad formats will strike a balance in getting more reader attention without driving readers away. One new format is the “pushdown,” recommended at a whopping 970 pixels wide by 418 tall on the page. When a user opens a new page, the pushdown ad expands downward, then rolls up to the top of the page. The second new format is the “fixed panel,” a sort of side banner that scrolls with you as you read up and down a web page — all 336 wide and 860 tall pixels of it. The third format is the “XXL Box,” a 468 x 648 window that includes video and other interactive elements to get reader attention (as pictured, apparently on ESPN.com, above).

The 27 publishers have all agreed to use at least one of these three new ad formats by July 1 of this year. They agreed to these formats under the auspices of a publishing trade organization called the Online Publishers Association.

But the new formats raise questions. The industry organization for developing ad format standards, the Interactive Advertising Bureau, is open to adopting these new formats, according to BusinessWeek, but so far the OPA appears intent on keeping the formats to just its members. It wants to differentiate what it views as higher-quality content from the rest of the web, and use these ads to charge a premium. Until today, standardized banner ads have been steadily making less money for publishers because social networks, blogs and all manner of other web sites are continually increasing overall banner inventory. Advertising networks are able to sell ads efficiently across any number of sites without having to go through the publishers. Standard ad units for banners may have made it easier for third parties to run campaigns for advertisers in lieu of these publishers — which some publishers believe has costs them money — but standards also allow advertisers to more easily coordinate widespread ad campaigns. Of course, if these formats prove popular, you can bet advertising networks and agencies will look to run similar formats across the web.

The OPA initiative is a sign of the times. Many other new forms of advertising are vying for advertisers’ dollars. Google has perfected ads that appear next to search results and pay based on actions users take. For many types of advertisers, this easily measurable method of seeing results has proven much more worthwhile than banners. Meanwhile, social networks like Facebook and MySpace are developing ways to target ads based on their users’ interests, activities and friend relationships. A wide range of behavioral startups are trying to gather more specific data about how subtypes of users behave on various types of sites. For example, ad networks like Federated Media sell industry-specific ads for niche sites like [disclosure] VentureBeat. Where these other advertising innovators are focused on targeted ads and audiences, these OPA advertisers may have hit on a better way to satisfy brands’ demands for more attention from the masses.