I don't think they are. If their Ps3 reviews are lower than their 360 reviews, compared to IGN, it is because the sites have different feeling on what is important in a game.
The pictures look incredibly close to each other. If there is a slight difference, how do you know that this isn't the case for all games? Shouldn't you check that out before claiming that the site is biased?
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS







