For now, while I use separate devices, I’m beginning to think of them as a single experience: pick up the nearest one and use it.
And that, I believe, points to the future of computing. It isn’t just having to decide which device of many to use. It’s a way of using devices that makes everything one needs to do simple, seamless, and that get out of the way of the task of the moment.
Randy Murray is right that this vision is closer than we might think. The limiting factor is ubiquitous Internet access, but here in the city I can pretty much assume that the device I have closest to hand has access to all my stuff. It's not seamless yet though, and I'm regularly stymied by our overly-locked-down work network that kills things like iMessage and iCloud syncing, and ultimately pushes me to use my personal devices (with their own cellular connections) rather than work-provided networked desktop machines. I imagine that I'm not the only one who's doing that.