Yahoo (NSDQ: YHOO) is powering a new ad product for Adobe (NSDQ: ADBE) PDF, a beta service for publishers launching overnight. (It’s literally called “Ads for Adobe PDF Powered by Yahoo!”) The idea: offer publishers the chance to include contextual, text-based ads next to PDF-based content and give advertisers in Yahoo’s network a new channel with a web-like ability to track ad metrics.  For readers, it could open access to PDF-based content that has been limited to paid subscribers.

The execution sounds simple enough: Publishers register and upload their PDF file (created in Adobe Acrobat 8 or earlier) so it can be “ad-enabled.” Ads are displayed in Adobe Reader or Acrobat in ad panel next to the actual content. Whenever the PDF is opened, the ad will be matched to the content.  IDG InfoWorld, Wired, Pearson’s Education, Meredith (NYSE: MDP) Corporation and Reed Elsevier (NYSE: RUK) are among the publishers participating in the beta, according to Adobe and Yahoo. One aspect sure to cause a fuss—it’s limited for now to U.S.-based publishers who produce English content. Release.

This strikes me as particularly interesting for a publication like IDG’s InfoWorld, which moved to web-only earlier this year.  InfoWorld sees it as a chance to create new revenue streams for existing products.

WSJ: “Until now, publishers could place ads in PDFs on their own, charging advertisers for static blocks of text or graphics that they would place in the document. But that meant the publishers had to sell the ads and lay them out on the page on their own. ... The revenue from the ad will be shared between the publisher, Adobe and Yahoo. The companies declined to give details on the revenue split.”

Reuters: It’s already been in private beta; the public test is expected to last for several months.

AP: “If the reader decides to print the newsletter on paper, the ads—which appear online on the side of the document—disappear. ”