Modeling Our World is likely the most authoritative text currently available about geodatabases. The sheer amount of information here and breadth of topics covered make it an excellent reference for anyone in the GIS field. Given its publication date of 2010 I was concerned the text would be out of date, but it turns out that's not the case. This is strictly a reference book. There are no exercises requiring a certain edition of ArcGIS software to complete, nor are there any how-to guides with screenshots explaining how to perform a task. The text simply discusses the overarching concepts in geodatabases. Projections, versioning, linear referencing, geocoding...the ideas behind all of these and more will not change, even when the software does. Perhaps the final chapter, which includes some Python code, will become (or maybe already is) outdated, but even then it would only affect 4 pages and still wouldn't change the fact you have to import a module or specify a workspace.
With that being said, the book's not perfect. Chapter reviews only appear at the end of the longest chapters, but having these at the end of every chapter would be better. A glossary would also be helpful considering how much is covered here, but there isn't one. Including 3 or 4 review questions about the major themes at the end of a chapter would help readers retain information, but there aren't any. Typos are fairly common, and sometimes the wording is confusing, requiring the reader to review a sentence multiple times to truly understand what the author is trying to convey.
For an example of the wording issue, see the first sentence of page 208:
"You use mosaic methods in a mosaic dataset to control what raster data is presented each time a mosaic (from the mosaic dataset) is displayed."
It's not that passages like this have any kind of technical error, it's that in the interest of being as precise as possible by eliminating pronouns and condensing everything into single sentences they've become unnecessarily hard to read.
Still, none of this negates the fact that overall the book is informative and useful. Full-color charts, diagrams, and tables appear throughout it. It's well organized, and outside of ESRI's online help pages you're unlikely to find anything on geodatabases this thorough. Modeling Our World explores the possibilities of ArcGIS and yet still only begins to scratch the surface - the numerous analyst extensions and spatial statistics barely noted here. The concepts aren't limited to a single version of the software, and given how it discusses them this book would likely be useful to users of other GIS software as well.