Google believes deskptop PCs will be redundant within three years.

According to a report by Irish tech news service, vice-president of global ad operations John Herlihy, made the comments during speech at the Digital Landscapes conference in Dublin.

"In three years time, desktops will be irrelevant. In Japan, most research is done today on smartphones, not PCs," he said.

Herlihy's remarks echo a speech made last month by Google CEO Eric Schmidt, who announced that the search giant is focusing on mobile, not desktop search, and urged application developers to do the same.

In his keynote at Mobile World Congress in Barcelona, Schmidt pointed out that global sales of smartphones and other mobile devices are growing rapidly and will soon eclipse sales of conventional PCs.

There's little doubt that smartphones are already ubiquitous worldwide. According to a recent United Nations report, nearly two-thirds of all humans currently use a mobile phone, and the mobile device revolution is still in its infancy.

OK, but is the desktop really doomed? Perhaps from the perspective of Google, a search company that generates nearly all of its revenue from online advertising, the desktop may soon grow irrelevant, at least globally.

Certainly, Google's strategic focus on cloud computing and connectivity is visible in every project the company undertakes, be it online productivity apps like Google Docs or an experimental fibre broadband network.

But it's likely the conventional PC will have a longer, healthier life than Google anticipates. Big bulky desktops are disappearing, of course, but that's hardly a new development.

Smaller, lighter, and more mobile laptops will take their place, except for niche applications that require maximum, local processing power and storage.

The smartphone is great for many things, but it's no desktop-replacement device, either in the home or office.

New mobile devices, such as the Apple iPad and similar tablets, may bridge the gap between phone and desktop. And laptops will likely make new inroads in developing nations, particularly as manufacturing costs continue to fall.

Who knows? Maybe we'll eventually ditch the 'smartphone' and 'laptop' labels and just call everything a mobile device.

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