Valve prefers open Linux to Windoes 8 & iTunes

Another day, another way for Valve to pile on Microsoft and Mac. It was recently revealed that the developer prefers open Linux to Windows/Mac.

According to a PCGamesN report, a Valve engineer - Drew Bliss - recently gave a speech at the Ubuntu Summit where he basically threw Windows and iTunes under the bus.
If you look at the way the world is going, Bliss began, where you see Apple completely in control of their system, and at least part of Windows 8 entirely controlled by the Microsoft App Store, Steam is going to be a little bit harder to do both in the store aspect and in the content delivery aspect.

We want to continue developing in open platforms, Bliss added, and so were looking around, and obviously Linux has become a very viable alternate platform. So we are now looking into doing Steam for Linux and supporting as many of our Steam games for Linux as we can.

Bliss concluded, We want to remove one roadblock that people have with Linux usage and keep the open platform alive. If Microsoft goes the way Apple has and Windows and Macintosh are, both completely closed ecosystems, Linux really is the best alternative for everybody. So we want to help it be as good a platform as possible.
What do you think? Do you think Valve is over-reaching with their assessment?