1 + 4 + 5 = classic disruption theory. The margins, cost structure, and organizations that have made them so successful so far are what's preventing them from seizing the tablet space. The CEO's are in place because they have made so much money from the old business.
MS and Intel are still aware of the disruptiveness of "Tablets" (a poor description for the phenomenon, but descriptive enough), but they are chained to their existing org-charts, ship schedules, and revenue streams. Whether or not they'll be able to pivot fast enough is still up in the air.
The really interesting aspect is that the important part in market growth isn't when the disruptive technology takes the lead in marketshare, or when it starts eating into the marketshare of the old guard significantly. Rather, it's the inflection points of growth that are important. When a big company is past its knee (still growing but growing at a smaller and smaller pace over time) while the little guy is growing at a faster and faster pace, that's when to pay attention, because lots of things happen quickly and by the time the marketshare starts shifting it's already too late, the die has been cast.
