Short answer: that's illegal.
Long answer: that's illegal, but how likely do you think it is the copyright holders (not necessarily the authors) will pursue you for copyright infringement?
The tricky bit is if/when you decide to stick ads on your site. Are you making money off their copyrighted intellectual property without any kind of licence in place to compensate them? Is your site a purely hobbyist site with no ads and consistently loss-making? That can sometimes sway a decision.
I would err on the side of caution. It's a civil offence in most places, but it's still a serious one which can carry significantly punitive statutory penalties.
NB: not every country has fair use or commentary laws (UK being a good example), so blogger emptor on all of those. I think the best thing you could do if you are going to include lots of copypasta from published books is at the very least liberally link through to their pages on Amazon etc, with lots of suggestions to buy them.
For me, the tipping point between acceptable and unacceptable when verbatim quoting another source is when you get to about 200 words, but that's purely subjective.