Game reviews are very important, just like reviews of any other product. It's an essential part of the commercial system, which I normally take part in. What's the point, though? Let's look at Aion again, while it's still fresh in our minds. Person A will read a review about Aion, agree, and hate the game. Person B will read the same review, agree, and love the game. So where do reviews get us? Nowhere. I waited a full month before getting into Aion, reading the forums, reading previews and reviews, trying to get a feel for what it was like. In the end there was no real option but to try it out.
Getting back to why I think reviews are important, I should qualify the statement: reviews that review relevant material are important. If you read this line in a review, be wary: "I think the grind in this game is awful." What this reviewer is saying is that 1) there is a grind (which there is in every game) and 2) he or she didn't like it. Neither of those two statements have any relevance to you, because your preferences and tastes will invariably differ from those of the dubious reviewer. A review should focus primarily on what the game actually involves, and what you actually experienced in it. The truly unbiased reviewer will allow people to draw their own conclusions about how they think or feel regarding those faithfully reported experiences.
Another point I want to make is that anybody who sees the negativity on these forums and is discouraged from trying Aion should remember the words of my old statistics professor: the people that make their opinions known are usually the ones that are the angriest. He was saying this to defend himself from mean comments on his RateMyProfessor.com profile, making the point that you can't get a statistically accurate feel for one's actual performance from these voluntary media. Nobody is going to go rant on RateMyProfessor.com unless they are really pissed off. Likewise, nobody is going to trash a video game on an internet forum unless they have had a particularly negative experience. You're not getting an objective feel for the game. The only way to do that is to play it yourself.