The Windows partnership between Nokia (NYSE: NOK) and Microsoft (Nasdaq: MSFT) apparently isn't limited to smartphones.

Taiwan's DigiTimes -- the tech trade publication that usually has a good read on what contract manufacturers are working on throughout Asia -- reports that the Finnish handset maker is working on a Microsoft-fueled tablet that may hit the market as early as the fourth quarter of this year.

Right away you may be thinking of Nokia blowing up the Windows Phone operating system that it's incorporating into its latest smartphones for a 10-inch tablet, but you're going the wrong way. This will apparently be a Windows 8 experience, making this a true tablet PC.

Apple (Nasdaq: AAPL) and Google (Nasdaq: GOOG) may be shaking their heads. Apple leans on the same iOS that it uses on its iPod touch and iPhone devices to power its iPads. It wouldn't dream of making the iPad run on the potentially clunky Mac operating system. Google is all about its open source Android platform when it comes to its market-leading smartphones and silver-medal tablets.

However, Windows 8 has been pitched from the onset as a tablet-friendly operating system. Sure, it'll obviously work well on desktops and laptops, but its potential as a game changer rests largely on the success of tablet PCs.

Desktop and laptop sales have stalled over the past year, just as "good enough" computing in the form of tablets and smartphones is booming. Microsoft is reportedly shelling out billions to get Nokia to champion its mobile operating system platform, but it's in the tablet space that Microsoft has a better chance of making a dent against Apple and Google.

Tablets are being used mostly for viewing video clips, surfing the Web, and playing apps. There are certainly some people relying on tablets for productivity suites, but there's a reason why the world's largest software company hasn't put out official Microsoft Office apps for iOS and Android devices. There were plenty of rumors pointing to an Office announcement earlier this month when Apple introduced the new iPad, but Mr. Softy appears to be protecting its flagship suite for a reason.

If Microsoft can hold out long enough for Windows 8 tablets, the devices would be logical purchases for regular users of Word and Excel. Sure, there are plenty of iOS and Android apps that allow users to interact with Office files, but nothing beats the real deal.

If Nokia wants in, it better not be late. Windows 8 itself should be out later this year, though there is no firm release date. Nokia was late to the smartphone party with an operating system that consumers actually want, and it's been paying the price for that with a share price in the single digits. If Windows-powered tablets are the next big thing, Nokia needs to arrive early.

Windows to your portfolio's soul
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