Yahoo announced they are closing down the Yahoo Publisher Network, which is the self-service contextual ad network that was set to compete with the extremely successful Google AdSense network. Yahoo's version has always been a failure when compared to Google, for many reasons.
Earlier today, Yahoo! emailed a small group of publishers participating in the Yahoo! Publisher Network self-service beta program (also known as “YPNO” or “Yahoo Publisher Network Online”), to inform them that we have decided to close the program effective April 30, 2010. This only affects our self-service platform for small publishers who syndicate our Content Match (contextual) listings.
At least, people will stop posting in the forums about how they can get accepted into the YPN program.