Good news, Apple (NASDAQ: AAPL) and Microsoft (NASDAQ: MSFT) investors: There's a new battleground in the tablet war.

At the end of the second quarter, 17.6% of workers were using an employer-provided tablet at work. That's according to a recent survey from U.K. researcher Ovum and up from 12.5% in last year's Q2.

And what of employees who don't have such generous bosses? Ovum says 66.7% of respondents who own a personal tablet also use the device at work. All told, 44.5% of workers surveyed said they owned a tablet, up from 28.4% last year at this time, Ovum reports.

"Even given the immaturity of the platform, tablet usage is fast becoming common practice in the enterprise, whether through BYOD or corporate provisioning," said Richard Absalom, analyst for Consumer Impact Technology at Ovum, in a statement.

Think of it as a new theater in the ongoing tablet war. Apple and Microsoft have the most to gain.

The Mac maker has a huge head start: Apple has sold more than 155 million iPads since introducing its first-generation tab in April of 2010. What's more, Strategy Analytics estimates there are now 40 million tablets hooked up 3G or 4G wireless networks in the U.S. The law of large numbers says most of these tablets are Apple iPads.

We'll see even more soon enough. Analysts put Apple's fiscal fourth quarter iPad unit sales at around 15 million, up from 14 million a year ago. Microsoft won't match that volume in sales of the new Surface RT 2 and Surface Pro 2, but the numbers also might come in better than expected. Ovum's data suggests that Microsoft is pitching tablet shoppers at an opportune time.

So what can investors expect? Not much initially. Microsoft had sold only $853 million worth of Surface tablets through June 30, and that's in spite of what appeared to be strong initial demand. That said, Microsoft also reported a $900 million writedown on Surface RTs last quarter. Apple, by contrast, sold $6.4 billion worth of iPads in the June quarter alone.

Surface 2 models might ramp sales some but there's no reason to expect corporate buyers to avoid iPads. Sure, there's no Office suite on the device yet. So what? We know one is coming. Meanwhile, Google has been offering a full range of Drive capabilities on iPads for while now, and Apple offers an iPad version of its iWork productivity apps. There are some 375,000 accompanying native iPad apps in all at the iTunes Store, according to data compiled by About.com. 

Therein lies the problem for Microsoft. Conditions may favor Surface RT 2 and Surface Pro 2 sales, but Apple's apps and installed base -- especially among the many consumers who use personal devices to work -- make it just as logical a choice for corporate buyers.

Do you agree? How do you see the tablet war between Apple and Microsoft shaking out? Let us know what you think in the comments box below.

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