IGN would be a good one. They hit almost exactly on the average statistically. To me magazines that underrank are more credible then those that overrank.
The average EGM review is around a 70.
The average Play ranking for s PS3 game is around 80.
7 sounds fine for an average game (I'd perfer a 6 but whatever.)
an 8 is just silly stupid... that's like old school Nintendo Power level.