I don't read reviews of games or films before I play/watch them, though I do look at review aggregates to determine whether or not it is garbage (I generally don't play games with Metascores under 70 or watch movies with Rotten Tomatoes scores under 60). I know they're not entirely reliable but I figure that it's a good way to filter out mediocrity.
NOW, I do like reading reviews AFTER I experience the film/game just to understand my own opinion better. They help me notice things that were particularly good or bad about the experience and as a result give me a greater appreciation.
It's a lot different with music however. With music I'm more lax about the general consensus (I like several albums that are merely considered "good" or "slightly above average" or even "completely insufferable") and I'll read reviews before listening to get an idea of how it sounds. This is actually one of the primary ways I have of discovering new music.