http://www.mackido.com/Interface/index.html [1]

It's old but still useful if it gets us to think

Compares the UI of Windows, MacOS 9, Next and BeOS

One thing about the mac idea of 1 menu at the top was that it was really a pain in the next when I was using my sister's ibook and had to move all the way for a menu with the touchpad when the app was all the way down. On the other hand, it saves a lot of space