[saetaes]

Has it really, or only in perception? Some proof of this would be nice. Last I saw, neither Apple or Linux have really made a huge dent in the consumer and business desktop space. Sure, they are more viable options than in 2005, but it still seems that most consumers are going for Windows, and businesses still buy Windows + Office.

[gamble]

Not on the desktop - but definitely on the server. The public Internet pretty much runs on Linux today, whereas Microsoft servers are all but confined to corporate IT departments. Imagine how much more money Microsoft would be making if the millions of web servers out there each ran a copy of Windows.