I agree wholeheartedly that the user interface is key, but I disagree that hardware is a solved problem. Displays still suck, after years and years of affordable options being just around the corner. Hell, I would LOVE to be hacking away at the user-interface issues (and thought a great deal about that during my Media Lab time already) but there just isn't anything on the market that I can wear around town without looking like a fool, no matter what software it's running. So why bother... I won't be able to use it anyway.

The next Jeff Hawkins is working on other stuff, because he knows that wearables will still be stuck be in the wooden-block stage for the forseeable future, absent a monumental infusion of VC cash to get over the chicken-and-egg hardware problems.

(Sorry, the above is probably too cynical.)

I also said physical design, making it look fashionable, was unsolved, and that no-one was working on that, either. :)

But the hardware to power that design and that UI? That's been solved for years, for sure.

I think the reliance on displays is a big mental hurdle, too, hence my multimodal emphasis.

Fair enough. I tend to mix physical design into "hardware problems", mainly because I have the tools to solve software problems myself, but not to do decent physical fabrication. A shorthand for "problems other people have to solve first". Heh heh.

I just don't see much of a way around the reliance on displays, though: humans can just take in orders of magnitude more information visually than through any other channel. It doesn't even need to be a GREAT display, to run Office in 1280x1024 24-bit glory... I could do marvellous things with the equivalent of an original 160x160 monochrome PalmPilot display, if it was always in front of my eye.

It's just so frustrating. If Microoptical and Lumus would get together, they could build The Perfect Display eyeglasses. But instead the focus is on trying to get you to watch TV from your cellphone...

You're absolutely right, we certainly can take in more information visually. The problem is that when something else moves or becomes active in our visual field, e.g. your HMD's news alert or something, it takes precedence, and you walk into a tree or get into a car accident.

This is why so many states have distracted driving laws: cell phones must be hands free and have voice dialing, the driver cannot see any of the DVD players in the car, etc.

Screens work best when you're not moving. If you've stopped moving, then you can probably turn your head to your arm, or pull out a screen from your pocket, or turn your glasses opaque and project onto them.

If you're moving, you should have other options for information transmission and input.

And if you're not moving for an extended period, you're probably at a desk, with a big monitor. So why not use that instead?