To that end, the mobile device is becoming a desktop of its own -- one where a significant subset of people's daily work can be accomplished. But it usually also works as an adjunct to a main desktop -- either a full-blown PC, or a Web "desktop" like a Gmail account. So, rather than just becoming a desktop of its own, it might be better to think of it as a piece of the desktop that can be broken off, reattached at will, and combined with Web functionality.
How this will develop depends on how effectively useful interfaces can be packed into small devices. A full-blown desktop interface on a device barely bigger than one's hand doesn't make much sense, which is why Intel and Google have both been putting a good deal of research into their Moblin and Android OS interfaces, respectively. Of the two, Moblin shows the most radical UI work and hints very strongly at how the future desktop can not only be portable, but truly useful on-the-go, and not just a glorified task-list or Twitter client.
What looks like the end of the desktop is only the end of one phase of the desktop, and the beginning of a whole slew of new desktops. What's also become clear is how "the desktop" was never just "the desktop" before, either -- it was meant to be many things to many different people's needs. The new desktops, plural, are preparing to satisfy those needs in ways that the old, singular desktop couldn't.
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