An adequate book, I’d say. All full-season official minor league ballparks are covered as of 2007 (which means that the new-in-2007 parks are mentioned, but not really described). (And yes, I know my review disagrees with zhejw about the coverage).
The Fodor book is better, though the coverage is less complete. Some of the older, similar, books are far better.
This short review was originally published on LibraryThing.