I agree with the first poster, this article has no useful content.
I subscribe to this feed for the articles. I don't mind adverts around the articles, or references to related O'Reilly books in the articles but this kind of item is just pure spam.
If you want to advertise your PDF book, why not write a good, useful introductory article about ClickOnce and then refer to your book for more information? That's the approach other articles take and I think that's perfectly fine and useful. Why break a good model from which everyone benefits?