I don't believe. They have money. Maybe the today's model of their business will be obsolete, but they will change before they become obsolete.
They have Skype, XBOX, Windows, Office, SkyDrive, Outlook, Microsoft Studios, etc. I bet an arm and a leg that they won't be obsolete, at least not at this century.
Windows has +91% of usage share of operating systems.
http://en.wikipedia.org/wiki/Usage_s...rating_systems
Like we say here in Brazil, for a good understander, a half word is enough.