I emailed YPN support this week and asked if I could use Intellitext or Kontera with YPN ads on the same pages. (Intellitext and Kontera ads are similar, they are contextual and usually appear as double-underlined links on a page)

Support replied they are NOT allowed on the same pages as YPN, in no uncertain terms. I can only use them in "other" pages on a site that do not carry YPN.

Another strike against YPN! (Google Adsense allows Intellitext and Kontera)