This just cannot be good for Microsoft. I don't see how this turns around. Windows 8 and the Surface are just not getting the traction expected to maintain their monopoly. For entrepreneurs, though, this creates a lot of opportunity. It also does for Apple, Amazon, and Google, of course.
One of my favorite books is The Innovator's Dilemma and here it is in action again. I consider this a must read for entrepreneurs. It will give you the confidence to go from a perspective of "that's already been done before" to "that's already been done before and can be disrupted because of the dependency on the old order" (Who Moved My Cheese?).
Here is the full article.