Million on 29 April 2008
There is no such thing as the "best" game.
best is a subjective word , what is "best" to one person may be undesirable to another.
I guess the only way you could objectivley [atempt] to decide the best game would be through sales numbers but even that would be a screwed up method because of the amount of advertising and promotion that goes into it( Halo 3 for example)
