Opencritic currently has it at 82/100. http://opencritic.com/game/4214/splatoon-2 People should use Opencritic over Metacritic because they are more transparent, and you can blacklist any reviewer you don't like from the aggregate score.
Edit: Nintendolife gave it a 10/10 but that isn't showing up on Opencritic yet. This should balance out Slant Magazine's terrible score of 6/10 (They gave BotW 6/10 too).
What a bunch of haters