I think it' s REALLY funny how Xbox fans seem to think that GameSpot is biased, when I see Ninja Gaiden get a 9.4 and Editor' s Choice, and Chronicles of Riddick get a 9.2 and Editor' s Choice, all just this year (CoR got a 8.5 at IGN). They also gave KotoR a 9+, and Halo is still one of the highest scoring games at that site.
The reason the " biased" thing got tossed around is because in the 6-8 months after the Xbox launch, which was nauseatingly bad for good games, and extremely hyped titles like Blinx and Brute Force turned out to be nothing more than average games, people thought they were " biased" when they got lower scores. The truth is that everybody gave those games lower scores than expected, and simply because GS is GS and they judge EVERYTHING on a harsher level, those games scored even lower at GS.
If you want to look at it from a PS2 angle, FF X-2 got a 9.5 from IGN, but only an 8.1 at GS; the lowest score of any major publication I can find. Onimusha 3 got a very low 8.3, and I (along with many other critics) thought it was one of the best action games of this generation. To be perfectly honest, the only bias I see at GS is within the PC realm, where just about every game (no matter how rehashed it is) is capable of scoring a 9+, regardless of the number of bugs.