usually i'll check the reviews of a movie or game before i buy it...
but if i decided to buy the game or watch the movie before checking the reviews, then my decision won't be changed most of the time.
If I'm going to go and buy a game or a CD or something like that, I usually read a review or two first. A reviewist's job is to review, so I trust that they will give a reasonably unbiased, educated outlook (unless it's a console/brand specific site or magazine, which should never be trusted.) I usually take reviews into account, but I also look at thinks like popularity, and my own personal taste. So I guess I do think reviews are important, to a certain extent.