Nobody can call when MS might not be here. They make so much money by default from business and the computer industry is as essential as the car and oil industries in our culture. Facebook is also an aggressive and powerful company who could take a lot of risks that we cannot predict. These claims are baseless. Could they both be gone in 20 years? Sure, but more likely they will transition into some other complex entity that will be a mainstay of our culture for some time. All of this could be superseded though if the world experiences drastic power shifts or war.