Other than the original discussion [webmasterworld.com] on this topic when the product was first released for testing over 6 months ago, I have not seen much response to this advertising format. Yet at least from Adobe's point-of-view [blogs.adobe.com] the noise level remains high. In fact, a few weeks ago they announced several interesting developments including:
Choose Match ads for the entire PDF to dynamically match one set of ads to the PDF and display this same set of ads on every page.. Or.. Choose Match ads for each page to dynamically match and display a different set of ads on each page.
PDF Access Guidelines
..if you rely on the ads to subsidize your content, you can restrict viewing of the PDF when ads cannot be displayed. In this case, a coversheet is displayed on the PDF which asks the user to download the latest version of the free Adobe Reader and/or connect to the network.
Embed Ads Within the PDF
In addition to displaying ads in a side panel next to your PDF content, you can now display ads within the PDF content itself. You will be able to place the ads exactly where you want them in the PDF.
Bulk Ad-enablement of PDFs
If you have a large volume of PDF files, we offer a desktop application that will programmatically upload PDF files to be ad-enabled. The application allows you to specify an outbound FTP server folder where original PDF files will be retrieved for processing.
This format really intrigues me. For example, anyone doing self-publishing consider what your book makes you per chapter; not the selling price but your own revenue. For some I've talked to this is probably less than 50 cents per chapter. I would certainly think that it is possible to make this same amount if not more if chapters are given away for free with ad support.
But at this point I can't seem to find any good feedback on results.
One big concern I have is that ads seem to be all based on a per-click model. Since what I do would generally be printed out, I would want a per-impression option.
[edited by: PaulPA at 8:40 pm (utc) on July 16, 2008]