access to a pool of games doesnt mean anything, if anything it'd mean that those quality games really do stand out and matter when you look forward to them and finally get them and bad games/subpar games dont really have a spot on your gaming schedule anymore, thats what i have gotten out of having so many games, in the end you have less, but those few really matter.
getting back to the halo 2 review, professionals have to see it a lot differently, they have to be unbiased as possible, some of us know how that goes a lot dont. magazines, internet writers have to score this game fairly, for the flaws it does have it cant be overlooked just because the game is so awesome ya know? it already got great merits in the areas that matter so im okay with anything anyone throws out there. egm will prolly give it 10 across the board and i expect 9.5-10 from game informer. but look for similarities between each review and youll see where the achievements/failures really lie.
just remember in the end, thier score is just thier opinion, take it for what it is.