Metacritic doesn't just aggregate the arbitrary scores that professional reviewers assign to subjective works such as video games. It aggregates the arbitrary scores anyone can apply to subjective works such as video games. This has all sorts of fun applications, such as abuse. So, recently Metacritic banned a bunch of spam accounts set up to slag Bastion and Toy Soldiers: Cold War for no good reason.
According to Giant Bomb, Supergiant Games and Signal Studios both noticed that their aggregate scores, among users, had fallen after they publicly asked fans to rate their games on Metacritic, whose ratings are frequently cited by industry executives and flacks and in some cases govern compensation. After fielding complaints, Metacritic looked into the matter and found both had been pummeled by 0-rated reviews, without written comments, from a fresh batch of accounts. In other words, it was a hit job. Metacritic promptly banned the group of user reviewers and removed their scores from the games' averages.
This is all well and good, and it's nice to see that Metacritic wiped out this slander of two of the summer's best downloadable titles. A written user review that spells out someone's specific praise for or disappointment in a product, whether it's a video game, a film or an appliance, has merit because another reader might identify with the writer's experience, or might be looking for specific qualities that a professional reviewer doesn't address in speaking to a broad audience. But aggregated user reviews, especially considering their potential for abuse, are even more useless than the jury-rigged consensus of professionals that Metacritic provides.