In their SEC 10-Q filing, Microsoft wrote

To the extent the open source model gains increasing market acceptance, sales of the company's products may decline, the company may have to reduce the prices it charges for its products, and revenues and operating margins may consequently decline

My personal view is that Microsoft is under estimating the threat, not only to itself, but also to the world economy.  Think of open source as a virus that has yet to fully transform itself.  Those who are trying to take advantage of open source movement, companies like IBM and Sun, are riding a tiger, unable to get off and destined to be feed its hunger.  As grassroot organizations, companies, and governments build and add to open source infrastructures, nature of the beast will change, destroying value faster than we can build it.

Open source is not like Pet Rock or Hoola Hoop.  Open source is more like Communism or Fascism in its nature.  Can anyone or anything stop it?  My current view is that only a total wreck of the world economy will stop it because open source is fueled by idealism and subsidies from outside the software industry.

If the reader thinks I am anti-open source, think again.  I like open source and continues to contribute to open source community.  What I am saying is that open source is as dangerous as wildfire and should be treated as such.  While destruction and evolution are often confused in times of fast changes, caution and skepticism may be our guiding light.