My personal theory is video game journalism is young enough to have largely missed the old fashioned long-form investigative journalism phase, so there isn't even a history of strong journalistic integrity.
Edit 2: there are also video series about video games that are neither reviews nor consumer-oriented funny (or "funny") news programs but rather try to provide insight into the medium. See, for example, http://www.errantsignal.com/blog/.
I think the real journalism involving videogames wouldn't be regarded as "videogame journalism". Cultural issues like misogyny/portrayal of women, working conditions for developers and QA, and similar important issues are likely to be handled by "outsiders". Videogame hardware is assembled in Foxconn, too, after all.
But it helps that the blogging/website proliferation makes reviewers and reporters (I refuse to use the term "journalists") more independent of the publishers and videogame developers.
It's getting harder for publishers to control the press, which is probably what we are going to see with this event.
This is roughly true. There's a movement struggling for prominence to perform serious criticism, but it's been in the academic sphere rather than the consumer sphere... so no one makes any significant amount of money doing it.
I think additionally there is a large audience that reads reviews and other gaming news to be entertained more than to be informed.
It's fun to get hyped up and excited about some upcoming game, it's not that fun to read a review about a mediocre game.
And if you are largely going to make your purchasing decisions based on what your friends are doing anyway, or if a game isn't a super high-ticket item for you, then it's not something you really need to chase down professional reviews for.
