JavaRanch gives Release It! a perfect score, a full 10 out of 10 horseshoes.

Reviewer Jason Menard says,
Nygard talks about all the things that can and will go wrong in the finely crafted software we were sure was ready for production. A full two-thirds of the book is focused on capacity and stability issues including patterns and anti-patterns for both. The remainder of the book deals with general design issues as well as maintaining health and status in an operational system. “Release It!” provides many first hand accounts to illustrate his points, beginning with the Exception that grounded an airline, and these stories serve as excellent motivators. It’s better to learn from the mistakes of others, and I really appreciated the detail Nygard went into addressing some of these horror stories.

The Pragmatic Programmers have a few “must read” books and “Release It!” is another one.