As mentioned, it's not GameSpot, it's the reviewer.
1. He normally reviews sportsgames
2. 8.2 is pretty much his highest score (see for yourself at:
http://www.gamespot.com/users/AaronThomas/contributions?mode=reviews). So in some respects, you could see this score as a 7.5/8.2 which is about in line with the rest of gamerankings.
If you were really, really trying hard to find some bias, then it would have to be that GameSpot doesn't consider the game important enough to be reviewed by someone more suitable. It would have been more interesting in that respect to see Jeff Gerstwin review the game, because he did the last PS2 review and he's still with GameSpot. This also shows in the fact that he also got the Heavenly Sword review, though ironically, he seemed to have really liked it, as he gave it an 8 which as we know is just about the highest praise he has given games in his already considerable GameSpot career.
Which leads me to
3. He's clearly personally not biased against Sony. First of all he'd have reviewed Heavenly Sword lower than his 8-out-of-8.2, and second his reviews of PS3 sports games are rarely lower than their 360 counterparts, unlike with some other reviewers (irrespective of whether or not that is justified, as clearly it sometimes has been).
Most important thing to take away from this is that reviewers differ. There's a slighly interesting idea in determining bias towards a certain platform from which games get which reviewers, but it's at the very least not suited for this thread.
Lately the whole reviewing bias thing has been getting a little out of hand, so I propose we do the following things:
1. Keep the game's main thread reserved for mentioning and linking to reviews, and discussing the actual review content. If you disagree, preferably wait until you've played the game yourself and come with your own impressions.
2. If you must discuss review bias (as it's not a totally useless subject of discussion) then:
a: do so in a different thread (which at the very least has the advantage that the mods can then just lock that thread, and it doesn't affect the main thread)
b: do your homework. Look at the reviewer's history, the website, how previous games in a series did on the website, and so on.