That is an interesting point which I had not considered. I am not sure pull down menus with icons wouldn't have worked, too, though
Honestly my only problem with the ribbons is that they are impossible to scan for what you need (ie scanning left-to-right is not natural, and the icons are not ordered in a single dimension). Vertical ribbons, maybe? Oh, and please tell me what the hotkeys are
With an OS I suppose there will be fewer options you need to go hunting for (as long as they don't do something stupid to Control Panel), and maybe the ribbons would annoy me less.
As for the new user argument: I've never really understood this. For computer-illiterate people, it does not matter what you put on the screen. They will never find it. [edit: what I mean is that graphical icons cannot
correspond with most technical commands. What does 'copy' look like? This is the same reason road signs are still not universal. What does 'speed limit' look like?] With computer literate people keywords seem optimal. But I guess that's the whole old argument coming back in. My mantra: choice