"New Tricks" has a slow, introspective pace to it that some will love (it has a nice noir-ish feel), but won't be to everyone's taste. The plot is solid and enjoyable. While I was able to guess at the culprit, there were sufficient red herrings and questions remaining that I was never entirely sure until the end. The world is wonderful---it has a smoky urban fantasy feel, with Mason's beloved jazz curling in-between the pages (I probably would have gotten even more out of the book if I knew much about music, but that lack of knowledge didn't interfere with my enjoyment). The characters---particularly the side characters surrounding Mason---have plenty of life to them.
Mason himself is an intriguing hero. His reactions to things were very much not stereotypical, particularly not young-single-male stereotypical, and that made him a fantastic lead character.
Unfortunately, my one real complaint is that the villain didn't fare so well at the end. Which is odd, because there were plenty of indications of depth before that. Somehow at the end most of those dimensions dropped away and we ended up in cheesy villain land. This doesn't stop me from recommending this book, however, as the majority of it is quite good!