By Daniel Eran Dilger

Published: 09:00 PM EST (06:00 PM PST)

Microsoft's Windows 8 is still a year away, but IDC is already predicting that the new release will be "largely irrelevant" to conventional PC users and that its ability to sell tablets will be "disappointing."

While bullish about Microsoft's prospects for selling server editions of the new Windows 8, IDC states that "Windows 8 will be largely irrelevant to the users of traditional PCs, and we expect effectively no upgrade activity from Windows 7 to Windows 8 in that form factor," according to an overview of the report by Computerworld.

The reason Windows 8 is expected to stoke so few upgrades is because it won't offer much to existing PC users, aiming primarily at giving the existing Windows 7 a layer of "Metro" styled interfaces that Microsoft hopes to enable Windows to ship on iPad-like tablet hardware.

In addition to adding the Metro interface, which originated on the Zune before being adapted to Windows Phone 7 last year, the other major change in Windows 8 will be new support for ARM processors, enabling "Windows" to run on a new class of battery efficient new mobile devices.

"There will be intense scrutiny on Microsoft’s ability to deliver a successful tablet experience aboard both x86-based tablets and on devices running ARM processors," IDC notes in its report, which states that the firm expects Windows 8 tablet sales to be "disappointing" next year.

"This is a tall order for Microsoft, and while the x86 tablet strategy makes sense as a transitional solution for today’s PC users, it will be the ARM-based devices that need to shine and clear a high bar already set by Apple.”

iOS vs Metro mobile devices

However, porting Windows 8 to ARM won't enable new devices to run existing Windows desktop software, all of which will need to be rewritten for the ARM chip. Apple faced similar issues in porting its Mac OS from 68k to PowerPC and eventually Intel processors, but at each transition, Apple included software to run existing Mac titles in emulation. Microsoft has announced it will not.

Apple also ported and refined Mac OS X to ARM-based mobile devices, rebranding the platform as iPhone OS and eventually iOS. However, Apple has never attempted to shoehorn existing Mac apps on iOS, instead rebuilding its own apps from scratch, suited to the unique environment of the iPhone, iPod touch and iPad. Microsoft has issued conflicting remarks about its software plans for Windows 8 tablets.

Apple spent years bringing its Pages, Keynote and Numbers apps from iWork and its iMovie and Garage Band apps from the iLife suite to iOS as mobile-optimized, touch based apps. In contrast, Microsoft has only suggested that it is still in the early conceptual stages of contemplating how its flagship Office apps might run in Windows 8's Metro environment.

Microsoft may ditch consumer PC market to focus on enterprise, licensing

The expectation that Microsoft will do well in selling Windows 8 to the server market but fail to entice consumers or IT departments to upgrade their desktops (many corporations have just finished upgrading to Windows 7, and typically plan to skip every other version of Windows, as many did previously with Windows Vista) could further entrench Microsoft into an enterprise market niche.

Apple has continued to eat up PC share among consumers, effectively owing all sales of both $1000 and up PCs as well as the vast majority of tablet purchases. The popularity of MacBook Air and Pro models have also increasingly worked Apple's PC sales into enterprise markets, following a surge of iOS devices that IT managers have relented much resistance to supporting.

In reaction to the success of the iPhone, Microsoft has increasingly worked to license its technologies to support Apple's devices, entering into a high profile agreement to license protocols related to its Exchange Server for push messaging just as the iPhone turned one year old. This year, rumors have surfaced indicating that Microsoft will also port its Office suite to the iPad, following Apple's own efforts to deliver iWork.