I think 1998 takes it for me.
It does not include my favorite games in any category, but the games released this year had such an impact on gaming as a whole.
Ocarina of time, Half-Life, Starcraft and Metal Gear solid all where defining for their genres.
Even if Pokémon originally released in 1996, the first western release of the series was in 1998 marking the year it took over the world.
Tekken 3, my favorite non-smash fighting game left the arcade and entered our homes in 1998 as well.
Pretty much the only thing missing from 1998 is a major console release.