It should be 5, but ratings tend to get skewed between a combination of reviewers just pulling numbers out of their asses most of the time and the majority of publications not wanting to draw the ire of publishers and their readership by giving genuinely average but popular games low scores. When I did video game reviews for my school newspaper, whenever I gave a game the equivalent of a 6 or 7 (we used a 1-to-5 star system, but we could cut them in half, so it was really the same as a 1-to-10 system), I'd have to make it a point to stress that this actually meant above average in order to avoid confusion. When reading other people's reviews, I simply try to ignore whatever score they gave and just focus on their words, because I know it'll most likely be inflated.