A very good idea to earn money, thanks OP for this post.
There are many useful posts in this topic but I have hard time finding them, because they are flooded with spam. I am going to make a TOC of useful posts and post it here within a week.
This method is great for me. I am not a native English speaker and creation of 500 word post may take whole day for me. I have a full time job and can't afford to spend so much time now. Considering, that I am going to target very competitive keywords, I will not even think of seo and may even block my website from search engines. I will use content from review sites.
I think, that this method is not as easy as it seems, but if you want to earn money you must try hard.

Since I don't care about duplicate content issue I can use the whole web to generate content so It won't be difficult to create a content-rich web-site, which will seem legitimate to average users.
I will twist with method after making a research on affiliate marketing. http://www.blackhatworld.com/blackhat-seo/making-money/687867-ultimate-guide-building-amazon-affiliate-niche-sites-insanely-profitable.html there are some useful tips regarding how to build an amazon site with an example of a successful amazon niche affiliate site (http://pickmyshaver.com/).
I have one question with regards to web-site: Will amazon approve website, which contains only duplicate content?