In their last quarterly report, M$ blamed their recent revenue declines on competition from free software:
The Linux operating system, which is also derived from Unix and is available without payment under a General Public License, has gained some acceptance, especially in emerging markets, as competitive pressures lead OEMs to reduce costs and new, lower-price PC form-factors gain adoption
... Partners such as Hewlett-Packard and Intel have been actively working with alternative Linux-based operating systems. ... User and usage volumes on mobile devices are increasing around the world relative to the PC. OEMs have been working to make the Google Android mobile operating system more compatible with small form-factor PCs or netbooks. ...Certain 'open source' software business models challenge our license-based software model. ... To the extent open source software gains increasing market acceptance, our sales, revenue, and operating margins may decline.
They have complained about Netbooks and Google Docs before. They viciously fight Google, netbooks and all commercial gnu/linux but it is harder and harder for them to stem the inevitable rise of free software. Welcome to GhandiCom 3, "Then you win.""