I wasn't sure I'd get much out of this book, since I've already listened to the series of Dr. Sandel's lectures on which it's based. But I loved that series, and figured the book would be worth a shot. I'm so glad I did. Not only was the refresher worthwhile, but the final chapter (which is almost entirely new from the course) is a really great finish.
Sandel uses more or less the same disquisitive approach to the question of justice here that he used in the aforementioned course, and it's a good technique. It allows him to address a pretty thorny topic from a position of relative neutrality, and to proceed through some of the most significant historical thinking about it in an accessible way.
I also appreciated the boldness of his final section, because a more typical means of wrapping up would have been to feign complete neutrality, and resist taking any kind of stand. I suppose it doesn't hurt, either, that I agree generally with the stand he does take.