To many old-time mac users, this feature may not seem very noteworthy, but for beginnner mac users it is a god-send. The pre-Panther Finder is very computer-centric, requiring users to know about where the file paths of the Application and home directories. The Panther Finder is much more user-centric, hiding the system details from the user, if wanted. All a beginner user needs to know is that Apps are found by clicking the Applications folder, Documents should be stored in the Documents folder (with subfolders), etc. It is a much more straight-forward, coherent ideology.
Keep in mind that the people reading the O'Reilly articles are likely power users, who understand the file hierarchy in detail, but the average user isn't concerned. He/She just wants to store their documents and open them easily later.