I can understand why many people sound as though they were disappointed with this book. It's not a "practical" book, like Code Complete, Rapid Development, or Software Estimation, that you can immediately put into practice and improve your software's code or schedules.
But whether or not you agree with McConnell's conclusions about how to "fix" software development by turning it into a profession, like engineering, medicine, or law, I think it does a good job highlighting some of the ongoing struggles in developing software and making you at least think about them.
I agree that some of the solutions McConnell advocates seem overly-regimented and out-of-touch with what is currently often promoted as best-practice, namely agile development.
I also understand why people might think the author seems to keep going on about best practices, but never getting to the "real content" of telling us what those best practices are. From some of his allusions to them, they seem to be those described in Part 3 of Rapid Development.