I never quite understood the whole "I don't read reviews, I play the games I like." argument. I get what people stating it are trying to say, but it also comes off as smug and superior, as if they imply that everyone else is blind sheeple. Also, how do you know you like a game you never played? Sure, you might like the artwork, the overall concept and such, but the game itself still needs to be played before any actual judgement can be made.
Personally, I never put much stock in individual reviews. They tend to be skewed and subjective. However, agregate reviews can offer a reasonable idea of the game. Reading several reviews, both positive and negative, finding commonalities and information that all the reviewers agree on and in the end forming a reasonable picture of the overall quality of the game can help guide one's purchases for the better.
Of course, you should look for games that you like. If you hate JRPGs you shouldn't buy the next Final Fantasy game, no matter how well it's reviewed. I don't care how well a CoD game is reviewed, I'm not buying one. However, if a hot new RPG comes out and I like the look of it, you can be damn sure I'll go to Metacritic and read up before committing to the game financially.
Unless it's a Bioware game, then it's a Day 1 purchase...