"It's broader than just ARM," Epps said of Microsoft's publicly-discussed plans. "Microsoft's not parting ways with Intel. It will make Windows 8 run on Intel's SoC, too."
Even so, the demonstration Microsoft put on at last January's Consumer Electronics Show focused on Windows running on ARM designs. While Steven Sinofsky, who heads Microsoft's Windows group, gave a nod at the time to Intel's current Atom processor, he saved his enthusiasm for ARM-based SoCs.
Among the chip makers expected to compete for Windows tablet dollars are Qualcomm and Texas Instruments.
"I don't know whether Microsoft will support legacy apps, all the various Windows executables, in Windows 8 on all SoCs," said Epps. "My impression is that they will. But I don't know if that's a realistic expectation."
In January, Sinofsky only promised that Microsoft would create a version of Office that runs natively on the SoC edition of Windows 8.
But even if Microsoft makes a break with the past -- as did Apple when it launched the iPad -- and doesn't support "traditional" Windows software on tablets in 2012 and beyond, it won't be the end of the world, Epps said.
"While the consumer expectation is that [the next version of Windows] will work with all their stuff [on a tablet], they are also eager to embrace something new," she said. "They realize that the pace of technology demands that."
As examples, Epps cited RIM's decision to not support old BlackBerry smartphones with the BlackBerry Bridge software for its PlayBook tablet, and consumers' eagerness to adopt Apple's iPad, even though that tablet can't run Mac software.
No matter what it does, Microsoft has a shot at making it big in tablets, Epps said.
"The fact is, Windows is the number one operating system people want on a tablet," Epps said, referring to a survey Forrester published two months ago after polling 3,800 people. "That may have surprised people, but that's what the data shows."
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