I ocassionally read Gamespot to be aware of new releases and to read game reviews. The problem is that game reviewers tend to rate the games based upon graphics, sound and playability as a whole; that is certainly not a bad thing, but it may happen that some game that gets rated as "poor" or "disappointing" ends being your favorite just because you 'liked it'. Sometimes you unconsciously put aside the game's flaws and simply get to enjoy it, regardless (until some point) of the mixture graphics-sound-playability. There's no way to measure this; it depends on each person's point of view. It's like your 'unconscious review' of that game.
In short, it's good to read game reviews before playing a game (I tend to do that always), but that can't stop anyone from actually playing it.