Apple's newfound fortune was built on the understanding that mobile computing is fundamentally different than desktop/laptop computing. That understanding is the reason they were able to break touch screen interfaces into the mainstream.
Steve Jobs is laughing in his grave at stuff like this.
Form factor is just the topping. Using web apps and cloud storage is so far the most accessible way to have a seamless computing environment (versus experience, which must be different like Jobs knew). Apple or anyone else could side step those entire industries by making powerful portable smart phones that acted as a driver or data storage for other operating environments.
None of that solves the problem of being vulnerable to issues in the cloud, though. There are about 10 billion things that have to work correctly for your data to be accessible and safe and only 1 or 2 things that have to go wrong for it to be gone forever.
Which is true for local storage as well. If fact, I will argue that data on cloud is more reliable than data on my local machine. I carry it all the time, I don't have back up for a large part of it (I use versioning for code, everything else is painful); I did have some backups on external storage devices but they are more prone to faults and crashes than my internal drives. Carrying such devices around is a major hassle - actively taking backups is an even bigger task!
I'm not suggesting they need to be fundamentally the same.
Apple has taken steps to give iOS and OSx some key similarities in look and feel, the lines don't need to be blurred any further, in fact for this concept to be successful, I don't think they should.
People are taking you awfully literally here. I think the idea of only having to ever configure and trust 1 device is fantastic.
I guess people are thinking of the integration that is available today and how awkward it is, rather than the integration that can happen when everything ships with support for working with everything else.
Sure the software needed at the center of it doesn't exist, but there isn't any fundamental limitation on presenting device appropriate interfaces, it's just integration work.
I really don't believe a company like Apple would be more than five years away from being able to do something like this, either... Provided they wanted to, of course.
It still may be too soon, and I'm certainly not thinking the device in the linked article is the solution, but there are a lot of possibilities here.
Steve Jobs is laughing in his grave at stuff like this.