A reviewer takes an objective stance at detailing a game's features.
A critic takes an objective stance at the game's faults and provides constructive criticism on how to fix them.
Does Yahtzee do reviews? Yes, but not in detail.
Does Yahtzee do criticism? Yes, but a lot of it tends to be biased or incomplete.
Don't get me wrong I like Zero Punctuation very much and I respect Ben's wisdom regarding what constitutes good games, yet I get the feeling the majority of the games he goes over is more akin to nitpicking rather than genuine critique.