Looking at the state of how games are scored I full disagree with giving games a number whether scoring out of 5, 10 or even 100. The issue I have with this is two-fold number one the scores are skewed and number two that scores are not properly weighted.
Starting with scoring being skewed on a 10 point scale a 5 out of 10 should be average with a 6 being above average up to a 10 being perfect or near perfect. Unfortunately this is not the case with multiple games that were average receiving scores of 7, 7.5 or 8 out of 10 and not 5. Using Dragon Age 2 as my example as I found that game to be wholly average over all it received an 8.5 out of 10 by IGN yet Duke Nukem Forever which was by all accounts a disaster 12 years in the making received a 5.5 out of 10 by IGN, which by a non skewed scale would in face make that game average. I think a lot of this comes down to publisher money, look at IGN as the worse example of this and you will find full page banners for a game plasters all over, flash video ads and promotional coverage leading up to the games launch. All of which was bought and paid for by the developer, there is no way that IGN is taking that money and letting their staff give the game a 5 out of 10 if its average.
My other issue is with how scores are weighted by aggregate scoring sites like Metacritic or in the case of other media Rotten Tomatoes a 5 out of 5 is not a 100% score. A game that receives a 5 out of 5 or even a 10 out of 10 might still have flaws that keep it from being perfect, but as far as Metacritic is concerned a 5 out 5 is a 10 out of 10 which is in turn a 100 out of 100. Now this in turn again means that an average game on a 5 point scale would be a 3 out of 5, but maybe that game would have scored a 5, 6.5 or 7 on a 10 point scale, but a 3 out of 5 would be 60% which would be a 6 out of 10. This is of course ignoring the fact that Metacritic skews there own algorithm to give some sights more weight than others.
All things considered I find numbered scoring to be a flawed and useless metric, instead I will rate games based on the following simple terms: buy it, try it or pass. A game which I give a buy it rating is one I believe to be a best example within its genre and while not perfect I wholly believe it to be worth every penny if you choose to purchase it. A game which I give a try it rating I believe a die hard fan of that genre will love, but a casual fan or curious consumer should probably wait for a price drop or sale and a game that I give a pass I found to be broken or a waste of time for anyone to bother with. In note my personal tastes should be considered here as well, as always I would urge a consumer to seek alternate opinions and to make informed decisions as a consumer.