Which in turn comes from the adoption of handheld devices, which must be usable one-handed because "handheld" ties up the other hand acting as a support.

The theory behind changing desktop OSes to match the mobiles is, ironically, in pursuit of the ideal that you espouse: Standardization; minimization of variety in user interfaces that must be learned. The mobiles aren't going away and they won't be equipped with antigravity stands and holographic two-handed keyboards any time soon, so the one-handed gestural interface is going to become the new standard. End of story. For about a decade.

User interface designers pursue the Holy Grail of the user interface that you don't notice, and that you don't have to be taught. For decades that was thought to be based on literalism and icons that supposedly depict real objects: Folders, pencils, documents, ad nauseum. You're right that it's fallen short of the goal. Icons turn out to be culturally-specific, as well as just damn difficult to make communicate an idea in a few dozen pixels.

The mobiles seem to be headed toward a different kind of literalism, based on touching..."touching" things through the touchscreen and gestures, even if the things you manipulate are more abstract. I don't know if your Kindle has the full Android interface, but if so, I'm talking about things like sliding panes left and right, or best of all, two-dimensional scrolling that feels like you're sliding a piece of paper around on a table top. About the only equivalent to a mouse that I can think of is that a click is equivalent to a finger-tap. Everything else is a new kind of interaction.

I hate to break this to you, but I'm working on redesigning the Zone UI along these more modern lines. In part I'm looking ahead and seeing that in a few years UIs won't be based on point-and-click, and OSes like Windows 8 are going to force me to adapt. But also, of course, now that I have a device with 1024x600 screen and a gestural interface, I'm looking forward to the challenge of creating a new UI for the Zone that looks good on my Galaxy Tab.

You'll have plenty of opportunity to get your hands on the prototypes and give me feedback. At the moment all I have is a mockup that doesn't display live message data. Give it a week or two. I promise it won't be a horrible experience for you.