playBunny: We won't all have the same rating, since if you lose and your rating goes down, you will gain more next time you win. Since there is some skill in the game the list will still be meaningful, though not as much as another system may be.
In fact winning 65% of games against average players is the problem, and there are undoubtedly players with inflated ratings as a result (for all I know I may be one :)