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Very intriguing article about the impact multi-touch tablets are having on the 3d/design software industry:
http://architosh.com/2011/08/the-ipad-how-the-cad3d-industry-is-being-changed/
To me, the user-interactive capabilities of these devices provokes a completely new way of thinking about design tools. A similar comparison is the evolution from coordinate-based drawing in AutoCAD to the user interface of Rhino’s Grasshopper plugin. Back when I began using AutoCAD, it was DOS-based, release 12. If you wanted to draw a building component; it usually started at the ‘command’ line with something like this: line<enter>@12.5<45<enter. There was a separate AutoCAD language that users had to learn and use to make anything. In Grasshopper, AutoCAD’s antiquated, coordinate to coordinate drawing system, has evolved to an interactive, modifier-to-object-to-relationship drawing system.
In the Grasshopper scenario, the user does not just draw what he wants to see, instead the user is setting up relationships and rulesets to generate the geometry. Similar to the big change from DOS to Windows, the multi-touch operating systems offer a completely new and different level of user interactivity and capability. Back in 1994, it was difficult to imagine an interface such as Grasshopper, and I look forward to seeing how design interfaces evolve with the popularity of tablets such as the iPad