In his introduction he does talk about if you need Photoshop 7 to purchase the book or can someone use Photoshop 5 and use the book and he lets the reader know that in previous books, to make certain shapes you needed to go through quite a few steps but with Photoshop 7, it's much easier and less time consuming to do certain tricks which he had in his previous books and also he has added a lot of new tricks using the latest Photoshop version.He also points out the advantages of Photoshop 7 and how the newer features will benefit photographers but he mentions that P6 owners can take advantage of the book.
I like to think that I know Photoshop very well but what I love about his book is learning how he does certain tricks so quickly, I seem to do some of those tricks in a more time consuming manner. So, to see his way of doing certain tricks definitely helps. You see, I'm not a manual reader and asmuch as I would like to sit back and learn every new feature of Photoshop 7, I don't have the time and maybe I'm just too hard headed that would rather learn on my own. And if you are like me, then you will definitely love this book.
Anyway, for those who are not familiar with his books. You don't have to read it like a usual book, just peruse the pages and if there is a trick you like, you can learn it. He explains step by step how he creates the trick and on each page at it's sides, there are tips for Photoshop 7 users and how to utilize the best image for print or web work.
Kelby takes a look at the current Photoshop trends that he sees in magazines within the last year and incorporates it into his book. From metallic effects to 3D effects to advanced shadow techniques and many of the popular effects you see on print and the web from popular fad/tricks such as the tv scan lines, Matrix text, halftone pop dots effect, glassy reflections and somuch more. Kelby's "Down & Dirty Tricks" has never disappointed me and has only been a big positive to adding his techniques to my print and web work but also to learn to do certain techniques quicker.
An excellent Photoshop reference book! Check it out!
Your only problem will be finding enough projects to incorporate your new skills!