I've noticed that people tend to rate products or services with either a positive or negative bias, i.e. they either start from the lowest possible rating and work their way up, or they start from the highest possible rating and work their way down.  I tend to be in the latter camp, which means I'll give a positive review unless there's something that really bothers me.  I was reading a review recently that equated to a 5 out of 10, but the commentary was all very positive.  I wasn't really sure what to come away with; was it a good product or not?  Because a 50% is a failing grade in pretty much any metric.