For me, there's a bit of a natural distinction: "workstation" tasks need a big screen and, at least for the currently foreseeable future, a mouse. "Casual" tasks need something personal, intimate, and "touchy". The world will benefit from having both.
This isn't to say that all tasks can be easily assigned to one of these categories, at least without further parameters specified: fingerpainting with Brushes and compositing 3D renderings for a motion picture are "the same task" in a sense. But each fits nicely with one device instead of the other. And, of course, there'll always be a gray area.
This isn't to say that all tasks can be easily assigned to one of these categories, at least without further parameters specified: fingerpainting with Brushes and compositing 3D renderings for a motion picture are "the same task" in a sense. But each fits nicely with one device instead of the other. And, of course, there'll always be a gray area.