This is, as far as I can tell, the first "official" book about NX-OS and the Nexus switch line. It's been two years since the products were first released, and one of the more interesting topics in my opinion (Overlay Transport Virtualization) is mentioned only once, on page 2. I realize that as of right now, that feature isn't officially available, but two of the authors actually work for Cisco, and I would have thought that perhaps there would be something more than just a mere mention of this forthcoming feature.
It's got the usual issues with a first edition tech book: typos, errors, what-have-you. All pretty minor. I was struck more by how much the authors assume the reader already knows. Options are mentioned, but not really described. They assume you already know what this stuff is. I suppose in my case, that's probably true, but for a book that calls itself "The complete guide to...NX-OS in enterprise environments", it seemed to be less-than-complete.
And for some reason, the font size of the index is about twice that of every other Cisco Press book in my library.