At the risk of sounding boring and pathetic, I have to admit that I also noticed that the Big Yawn reviews are all bunched in the middle. Well over half of all the reviews are in the narrow range of 7.0 to 8.5.
While there are decent reasons for this (zines tend to review music they like, or think they will like) and you will find this phenomenon at many zines, I think it's still a valid criticism.