I have an issue with the way people define "spam" as anything they don't like. Spam is a real and serious problem, and we dilute the importance of fighting it when we call anything remotely commercial as spam.
A blog has the right to make money. How? Typically ads and affiliate offers. As long as there is disclosure for both, I see nothing wrong with their use. OP wrote a review of a product and then submitted it to HN. People liked the review and therefore up-voted it. I think that's totally fair. Or are you suggesting that the OP is gaming the site?
The lack of comments may be explained by the fact that people didn't have much to add about the product, they are afraid of being labelled as SEO people, or they are simply toying with SEOmoz after reading the review.
HN-Books.com looks like a site dedicated to (mostly) book reviews. I don't see 10 posts a day from it, so I think it's totally okay.
I'm not crazy about bit.ly either in principle (for the reasons that you said) but again, the OP is definitely within his rights to use that service if he wants. Redirect links can be used for tracking purposes, for convenience, or very honestly for increasing one's conversions rates. Even in the latter case, I fail to see a problem with it.
If you don't like the content, ignore it (and if it's bona fide spam, then flag it by all means). If you like the content, but not the conditions under which it is provided, use AdBlock and don't click on the links. Screaming "spam" every time "commercial-ish" blog entries are posted is uncharacteristic and unbecoming of a community of entrepreneurs.