"(Full disclosure, I work there)"

I've been noticing this kind of disclosure becoming more commonplace, and it's beginning to bother me. No criticism at all of you: I'm sure you're trying to be ethical and ensure that there is no possibility that anyone might accuse you of a conflict of interest. I just wonder what purpose this serves. You offer a true, interesting, timely, and relevant bit of information. The fact that you work there doesn't change the nature of the information at all. Even if you got a commission on each book sold, which is unlikely, it still wouldn't change anything. O'Reilly's a great shop and this is great to know, in any case. So why this "disclosure"?

There are a lot of people who actually get paid to trawl internet forums and say good things about a company or divert people to that company's products.[1]

Declaring your affiliation is mainly a gesture of good faith, since it shows you've nothing insidious planned. In longer, discussion-type posts, it's an invitation for the reader to consider any biases the writer's affiliations cause them to have.

"Disclosure" type statements have always been common in specialized communities where decisions involving time and money are discussed. You see them all over the place in forums for luxury goods consumers (fountain pen enthusiasts, audiophiles, coffee geeks) and investors. When people start discussing the exchange of money or time for a specialized good (be it discount ebooks or paraglider motors), disclosures start to come into play.

[1] http://en.wikipedia.org/wiki/Shill

No Starch also has a sale: http://www.nostarch.com/ I am not affiliated.