Full disclose as well - Our family uses Linux on all our home computers for 5+ years for most things including productive office type work, school (both elementary and higher level education), multimedia and development. We have Windows for rare gaming. We use iPads for mobile/entertainment/gaming, etc. I use Linux and Windows at work. I have never consistently used OS X.
While I do agree that the impression is that Linux "can't compete with Windows in terms of "Productivity Software for Average People"" the reality is that the gap is getting much smaller all the time. Just one random example of Corel purchasing releasing Bible Pro and releasing it as AfterShot Pro establishing legitimate competitor to Apperture and Lighroom" and Valve confirming Steam for Linux (still vaporware).
In any case, my point was that if OEMs are squeezed by Microsoft from their established markets (Windows based PCs and HW) they may be pushed to position to make additional resources (money, marketing, support) available for non Microsoft solution. This may change the established impressions about such non MS systems. Using the "Live by the sword, die by the sword" analogy, the OEMs if pushed may become Microsoft undoing. Microsoft succeeded to avoid OEMs and challenge established vendors using their XBox and it assumes it can replicate the same success in tablet market.