If you are planning to type anything into a computer, you're hopefully not going to use a touch screen device or a tiny bluetooth chiclet keyboard to do it. As long as people want to type things into computers, the traditional ones with full-size keyboards and large, ergonomically positioned monitors aren't going away.
I couldn't spend 90% of my computing time at an iPad or any such device since I work a day job where I have to do a lot of typing into a computer. Another handicapping feature of these devices is that they won't run the software I want to use. Even if typing on an iPad touch screen that you either stare down at or lift your arm to reach wasn't the most ergonomically unsound idea since the stretching rack, I couldn't use it to compile and debug software in any meaningful way.
I'm not sure what meaningful thing I'd do at a computer if I had to spend 90% at an iPad. I thankfully don't have enough menial work to do to be able to spend any serious stretch of time doing it with a locked down, barely multitasking phone device.
Unlike many other historical developments of computer user interfaces -- going from knobs and jacks to flip switches, to punch cards, to printer terminals, to CRT terminals, to desktop computers, laptops -- the touch screen device is a massive trade-off in terms of efficiency and ergonomics. It exists simply because it's small and somewhat more flexible in terms of presentation than a tiny keyboard and a tiny screen.
