Hi,
This is already possible and documented here:
http://www.affiliatenichescript.com/doc ... tomization under the "CUSTOMISING CATEGORY PAGES" section.
Basically you create a new folder in your template directory called categories. Then you create a new .tpl file based on the category "friendly name".
So for example if your category is called "New Books" and the friendly name should be "new-books", you create new-books.tpl in /templates/deafult/categories/new-books.tpl
You can also customize individual product pages with the same method, creating a products folder and create a .tpl file with the name based on the amazon asin.