I found this excellent introduction to Touch UIs by Luke Wroblewski that looks at the disruptiveness of the introduction of successful input methods in computer history. In a nutshell, every time a new input paradigm was introduced to the market, market dominance shifted to those companies who used them to serve consumers best.
From Re-imagining Apps for Ultrabook™ (Part 1): Touch Interfaces
Over the past several years, both in my product work and writings, I’ve focused primarily on designing for mobile devices. Mobile has not only grown tremendously, but popularized new ways for people to interact with digital services as well. New capabilities like multi-touch, location detection, device orientation, and much more have made mobile devices a playground for new interactions and product ideas. It’s been an exciting ride to say the least.
Now many of these revolutionary capabilities are making their way to a new category of devices through Intel’s Ultrabook™ system and, once again, a new set of opportunities is available for designers and developers to re-imagine software. It’s an exciting time for desktop apps and I hope this video series will not only inspire you to explore new ways of thinking but help you with detailed design advice as well.
To start the series, we’re going to look at the opportunity touch interfaces provide for desktop applications. Specifically, we’ll outline the impact of new input methods in personal computing and walk through the top-level principles behind designing for touch.
http://c.brightcove.com/services/viewer/federated_f9?isVid=1