I’m currently reading the 1st edition from 2007: High Performance Web Sites: Essential knowledge for front end engineers.
In the near term, Chapter 4 (which talks about Rule 2: Use a Content Distribution Network) wouldn’t be applicable for smaller government organizations hosting from their own data center. But in the long term it would be a good concept to include within the basis of discussing a transition to federal cloud computing… ie., looking for a federal cloud which includes geographic diversity appropriate for getting front-end content closer to the users.
Chapter 16 (Rule 14: Make AJAX Cacheable) probably doesn’t apply either.
The other Chapters/Rules should be required reading for all Architects and Developers working with web applications. At 138 pages (including the two chapters which could be skipped), it’s a pretty quick read.
The author put out a second book in 2009, but it might be a little more advanced than what FSA needs to get started with: Even Faster Web Sites: Performance Best Practices for Web Developers.
Both of these are O’Reilly books. I’m reading the High Perf book via the IEEE connection to SafariBooksOnline. The author previously worked at Yahoo on web performance, and has since moved to the performance team at Google. He also developed the performance analysis extension for FireBug.