[jfoutz]

WRT affiliate programs, I've never had a problem with an book review that has an affiliate link to buy the book. If you're a plumber, and you found this great robot camera for inspecting pipes, sell it.

I think the main thing, if you're in it for the long run, is to preserve authenticity. It's easy to start seeming spammy.

[londonstartup]

Yes, totally. I just feel like a lot of e-books are 99p so 10% of that is so small. I guess the upside is 1,000 people could buy it at once, but then you'd need 100,000+ book fans for an ambitious 1% conversion. And even then you'd have to go author direct (so amazon don't also take a cut) which may mean lower quality books, and if people see you promoting bad product, end of brand, maybe.