Windows 8, Surface Tablets to Lead Microsoft's Fight for Relevance in 2013

"Microsoft's main weakness is that Windows and Office are no longer growing," says Kay, adding that he is doubtful that Microsoft can still invest in newer markets while shrinking cash cows maintain the company.

The biggest shock to Microsoft's system, he says, is diminishing Windows revenue over the past year, which will be particularly troublesome if Windows 8 fails to catch on in 2013.

"Windows 8 showcases touch, which is useful, but not in non-modern form factors like desktops, which are still widely used in the enterprise," says Kay.

This underscores the risks of putting the touch-centric Windows 8 user interface (formerly known as Metro) front and center on laptops and desktops, machines that have not made much use of touch-screens in the past.

"I'm just not sure the demand is there for touchscreens on laptops and desktops," says Miller. "But, to be fair, Windows 8 is only two months old so we should give it some more time to find its audience."