Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.

Let me give you an example: I've read this book with much expectation, it was very boring all through out the book
The answer to this example can be: Negative
Here is why: Review writer does not like the book because it was boring, therefore it is a negative review.

OK. solve this:
My first foray into this writer was her latest book, Scarpetta. I enjoyed it....so I purchased this effort and several others she had written. I was a bit disheartened to find that all of her books have basically the same formula and character studies. After a while reading her work becomes less than stimulating. It becomes trite.
Answer:
Negative