Re: Have only read one of those "33 1/3" books
the 33 1/3 books are the kind of book you want to skim before you buy, they're all vastly different from one another. Definitely don't buy them exclusively based on whether its about an album you like or not.
There are many good ones, but it's true that the bar is fairly low. Pretty much anybody can submit a proposal to write one. If I had an idea for one I'd give it a shot myself.