In that sense, Windows 8 will have to live two lives. Microsoft is expected to launch a Windows 8 version suited for ARM-based tablets. That version will be different from the desktop product, which will run on x86 microprocessors from Intel and AMD. This will create challenges such as forcing developers to create Windows applications for both tablets and desktops that will not necessarily be cross-compatible.
At its BUILD conference in September, Microsoft stated, though not very clearly, that Windows 8 ARM tablets will not run any x86 applications built for previous versions of Windows. However, Metro apps - touch-based apps designed for Windows 8 tablets -- will run on Windows 8 PCs.
In addition to such app compatibility confusion, Miller says, Windows 8 will simply be a hard sell on PCs because it doesn't deliver much more value than Windows 7.
"On the desktop, the multi-touch capabilities of Windows 8 will not be of much use," says Miller. "It is really an improved version of Windows 7 on the desktop."
But as an ARM-based tablet OS, Windows 8 has more potential and that's where the real pressure will be, says Miller.
"In order to convince consumers to buy a Windows 8 touch device instead of an iPad, Microsoft's partners must first have compelling devices at Windows 8 launch that are thin, light and fast, with very long battery life," he says. "That is a big challenge given what we've seen manufacturers offering up with Android-based ARM tablets over the last year and a half [all have been unsuccessful in curtailing iPad's dominance]."
Beyond the devices themselves, Microsoft must also build a strong ecosystem of apps to win over tablet consumers.
"It's the apps and the device together that make a device move in the market," says Miller. "If one or both are weak, it won't succeed."
Is Windows 8 Too Late?
With the operating systems release not coming until October, Windows 8 tablets may not even have a chance to succeed in 2012.
During the last quarter of next year, Windows 8 tablets will be a mild success at best, predicts Tim Bajarin, president of tech consulting firm Creative Strategies. But by that time, Apple will have released the iPad 3 and a variety of Android-based tablets (such as the Amazon Kindle Fire) will have evolved, too.
"If Windows 8 on tablets get any market traction, it will be in business," says Bajarin. "I don't see it having any real opportunity with consumers as its pricing is likely to be at the high end of the consumer tablet market."
For both PCs and tablets, Windows 8 is in a tough spot, says Endpoint Technologies' Kay. On the PC side, Windows 8 will be confronted with the "Why should I upgrade?" question from consumers and, more so, businesses.
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