This is one of the best technical books I have seen in a long time. Like a lot of people who have been around software development for awhile, there are areas where I am an expert and other areas that I have picked up enough on the way to just be "a little bit dangerous". SQL Server was one of the latter areas and I wanted to round out my knowledge and this book proved to be the perfect tool. Its unique "facing page" design means you can easily grasp the topic being discussed, and if it is one you are already comfortable with, just scan the code to make sure and move on quickly, or stop and read the details if needed.
I also recommend that you stop and do the exercises at the end of each major chapter -- they are worth spending the time on. They are well thought out and you may very well pick something up even in those areas where you may "think you know it" (I know I did).
Finally, the layout of the book and a detailed index means that this will be a valuable reference in the future -- I still don't aim to be a SQL guru, but I know that with what I learned and this book as a reference I will be much more capable than before.