The problem with ratings is it is subjective based on the raters experience. So to solve that just normalize the rating of each game by the average rating that person has given.... thus if a person rates 10 games all 10, then 10 is the average rating that person gives, so in actually, it would show up as a 5 across the board, or that all those games are just meh...
I do look at ratings when a new game comes on the market locally but reading the reviews is what sways me.....