I would actually say that this site's community is fairly Sony-oriented. In 2007 the site was dominated by Nintendo fans and most of the mods and users were Nintendo fans (and it was a pretty incredible moment when the Wii first passed the 360 in worldwide sales). Then MGS4 launched in 2008. It was the first time the PS3 ever had a really huge hit game and it was the first time the PS3 ever had a significant sales boost from an exclusive. After the sales disappointment of so many exclusive games (Lair, Heavenly Sword, etc.), seeing the success of MGS4 was like a blessing for a system that at the time was struggling greatly. There was a huge influx of PS3 fans after that game launched and the site has maintained a fairly strong Sony community ever since.
Really I think the community is pretty balanced all things considered. There might be fewer 360 fans than PS3 or Wii fans but overall I'd say we have a good variety of users on this site (well, except for PC gamers!).
