As I read through this (really excellent analysis), it makes me realize, even more, that PGs (and many others) thesis that it isn't so much the _idea_ that matters, but the execution.  The concept of a "User friend interface that creates a themepark for the users" didn't occur to Apple first - But, amazingly enough - Microsoft.  The idea of turning a computer into a themepark was basically the foundation for Microsoft BOB - From Wikipedia: "The user interface was designed to simplify the navigational experience for novice computer users."<p>Apple certainly seems to be executing on that vision in a entirely different manner than Microsoft did.