I want to do a blog using book reviews and incorporate amazon affiliate books. I have heard that it is a profitable market but I am not too sure. I was thinking of maybe doing books and movies all in one. Is this worth the effort?
You have to do a lot of volume to make serious money in books because of the low commissions per unit. The real benefit of doing books is to get yourself into higher commission tiers which makes you more money on higher-priced items. This is why I run multiple sites and blogs. My book site partially exists to get my unit numbers up so I make more money on software. (instead of making $10 a piece of software, I might make $11, etc.) Push books, but don't make them your sole focus. Use multiple sites with different product categories. I have been feeding Amazon customers for books I link to, and some are buying eBooks for the Kindle, which don't pay commissions.
Don't promote Kindle books because you don't get paid for those. Books is a pretty competitive niche.
I'm promoting one particular book right now and people end up ordering the eBook without any input from me! Something like 3 out of 12 orders.