For the most part, industry standard RSS is a very short list of simple XML elements. Standard RSS Readers only look for those standardized tags to create the display. You can verify that by opening almost any public RSS XML document and just looking at it. RSS is simple enough that you could probably pick it up by just looking at a well formed sample file and reading the short syntax document provided for free by the creators (UserLand Software for RSS 2.0 or the RSS-DEV Working Group for RSS 1.0 - FeedValidator.org has links to the documentation). After reading this title, I am a little confused as to whom target audience is supposed to be.
The first issue I had with the book is the coverage of versions. The author has chosen to write not only about the two current versions (1.0 and 2.0 - two companies, two separate tracks of standardized tags), but the preceding versions for each. I don't buy a Word 2003 book to learn about Word 6. The layout could serve as a reference guide for the tags when you're done, but again, the vendor provided syntax guides are easier to reference. Next, the author makes some assumptions that aren't publicized; you should be really (really) familiar with XML to understand many chapters in the book, and you should also develop in Perl (as there are numerous, lengthy Perl scripts used as demos). I've created many RSS Feeds for both company Intranets as well as Internet sites, and given the simplicity of RSS, I can tell you that you don't need either to create a feed on your own.
The back cover claims the book is a "step-by-step guide to implementation", but it really isn't. The author has written a very nice book on the general history and specs of standardized RSS, but then fills the remaining pages with a general syntax overview of other commonly used RSS XML namespaces (not really demo-ing them), ideas for extending RSS with your own XML namespaces (which is great, but really just produces a customized XML document that industry standard RSS reader's won't know what to do with) , and then transforming other site's RSS Feeds into your own conglomerated XHTML page with various Perl conversion scripts, SOAP tie-ins, etc.
For the percentage of people that already know RSS and are looking to really go into advanced manipulations - this is a great title and I recommend it. For everyone else who just want to quickly learn the very simple syntax, this is a misleading title and I would recommend saving your money and reading the vendor's free syntax guides, or talking a quick on-line course. You'll find RSS easy enough without this book.