I am still trying to figure out why people dislike affiliate links like these(if you were to put one in) It costs the person buying the book nothing and the person providing the link did some work to find the product and link to it thereby making my life easier. I am all for free and making my life easier.
The only reason that I can think of is that it detracts from the strength of the recommendation because of monetary concerns but since this is not the original person recommending it that should not matter.
If you consider all of the non-affiliate links to Amazon and all of the affiliate links to Amazon, I would hypothesize that more of the former are "genuinely useful" for their audience than the latter.
I agree with that. But the real question is if there were no affiliate links, would there be more or fewer useful links overall? It may be that money is an incentive to dig up useful links that nobody would provide otherwise.
http://www.amazon.com/Influence-Psychology-Persuasion-Busine...
I've read it and even bought a second copy to lend out. It's that good.