If Office were really on Linux I think you'd see Windows practically disappear.
Perhaps you're being a little too optimistic here.
Isn't that supposed to be windows 8.2?
Indeed. I have very little incentive to go from Windows 7 to Windows 8.1. Going to 9 (8.2) is not going to be much different since they still seem unable to figure out how to incorporate touch-based apps alongside classic apps.
Abstract ideas are concepts that need to be visualized, as they cannot be illustrated through concrete (real) examples. In a simple way, explaining the progression of logic in a (computer) program will be possible only if the reader can correctly visualize (imagine) it in his mind.
Then the implementation of an idea to a specific purpose makes it non-abstract and therefore can be patented. So it's not really the end of all software patents. Otherwise, further litigation might be required to establish a sound definition.