The Ribbon is amazing when you have lots and lots of commands, many which aren't always commonly used. Few programs approach the sheer number of commands. IIRC, in Office 2007 it was like 1300?

One of the main designers ran a blog explaining the design process. Even if you hate the ribbon, the explanation of how they came to it (heavily driven by telemetry, eye tracking studies, etc) is pretty cool. http://blogs.msdn.com/b/jensenh/archive/2008/03/12/the-story...