I remember the first time I read a book about testing. It was pretty eye-opening, and I remember it making me change or rethink many of my thoughts on testing.
Then I read another book, and those thoughts changed. Then I read another book, and I had more new thoughts and more importantly, began to form my own opinions. Over the years, I have discovered favorites - books that I recommend often, but I have come to the conclusion that the best learning experience comes from reading a variety of books on the subject (I suppose this is true for most subjects). It's not that the existing books are weak, or that none quite hit the mark. I have just found that knowledge of a combination of approaches expands the testing mind exponentially over a a knowledge of a single approach.
There are those in the industry, even those who have written books on testing, who say that there are no good books on software testing. I certainly don't agree with this notion, but I am thinking more and more that if you want to learn more about testing from books that you have to read more than one. I think it's too easy to head in the wrong direction with only one point of view as reference.
I have recently started giving the following advice in my senior tester course at Microsoft.
If you are only going to read one book on software testing...don't bother.
Perhaps I'm just an angry old man, but this makes complete sense to me.