That means jack shit. Job postings with Linux as part of the requirement have been on Valve's site for years.http://www.valvesoftware.com/jobs/job_postings.html
There are job postings requesting linux. I'm not sure how much of it is specific toward gaming, but just by clicking on random links I found Linux as part of the requirements.
If part of his job is using deceptive headlines to generate traffic, I will call him out for that.Stop bitching at Michael for doing his job.