Gaming communities are not well known for their inclusiveness, but how bad are they really? Which of the major sites are doing better or worse? Those are big questions to fully tackle, so I can only scratch the surface a little. You might call this a (very) rough pilot study about non-inclusive language in mainstream game blogs.
I looked through posts from this year at Joystiq and Kotaku. I was planning to analyse Destructoid too, but their search functions are inadequate for the purpose. From what I could see Destructoid are a pretty bad offender though. They sometimes excuse language in the name of satire (e.g., Gears of War is Gay). Satire can be used to reclaim language and highlight the ridiculousness of its use, but in these cases I don't think it's very clever or effective.