Falling for the hype?

So I have been roaming around the net recently and have started to see something I don't know how I should feel about. Alot of the advance reviews for Grand Theft Auto IV are coming out and almost all are giving the game perfect scores across the board. Now granted I have yet to play GTA IV and once I do you can be sure to find my review right here. I just find it hard to believe that everyone is giving the game perfect scores across the board as if there is absolutely nothing wrong with it in anyway. We know as gamers no matter how good a game is it cannot be perfect it's just impossible. Now I have enjoyed GTA games in the past however I got fed up with the series after seeing the games were more or less rehashes of each other with minor upgrades.
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So this begs the question. Why is the game getting such perfect reviews? Have the reviewers fallen for the hype and are overlooking every little bad thing in the game as a result? Are they all GTA fanboys? Do they really like gangster stories? Or is the game really that good? It amazes me that a game like Bioshock that I and many others consider a masterpiece didn't get scores as high as GTA and Bioshock did alot of things games had never done before. Even if GTA IV is that good it's just another GTA it's basically the same game GTA has always been just with way more spit and polish that the power of next gen allows.

I don't know maybe I'm selling GTA IV short and if that's the case we will all know once I get my hands on the game for a reivew.