Hell, no. His "Reviews" are strictly entertainment. He also strikes me as having a fairly poor taste in games. He didn't even play FFXIII before reviewing it, and just because it's popular, he ignores that Halo actually has a strong story and great setting.Not only that, but listening to reviewers is generally for the thick-skulled, brain-dead, sheeple gamers. That score is a representation of someone's opinion that is completely different from yours. Are you REALLY going to let that influence your purchase, or worse - are you going to believe that their opinion is better than yours? That you should mold yourself to their idea of perfect and shun things that are actually fun to you? I've let reviews influence my decisions about five times, and it's almost always been just awful. I got one good game from that tactic - Resident Evil 4. The rest were just godawful games like Mass Effect, Final Fantasy 12, and Gears of War. After those train wrecks, I haven't let critics influence my decisions ever again. Basically, reviews are only useful for weeding out games that get low scores (less than 5/10) from a wide variety of sources (at least 5).
The CORRECT way to go about buying games you aren't sure of:
You are a gamer. You SHOULD have some gamer friends.
-Some of them have terrible tastes: I've been trying to get this one kid to download Castlevania SOTN for three years, but he always counters with "Nou need to get so-and-so generic piece-of-shit game." He's obviously a dumbass, and I avoid games he recommends like the plague.
-Others have much more appreciable taste: Try to think of the guys who recommended your first Final Fantasy/ Legend of Zelda/etc game or goaded you into borrowing a game you truly loved. The people you always talk with about playing your favorite games. If they're telling you to buy a game, you should probably listen. If they played/are playing a game you're thinking about, you should go to them to hear what they have to say instead of some reviewer you've never met.
Also, don't be afraid to let your intuition make a choice every now and then. I almost didn't buy FFXIII because FFXII was such a steaming pile. A couple days after release, I saw the commercial and thought "Wtf am I doing? This is a completely different game. That commercial looks fucking awesome." So without any influence outside of commercials and Square's previous games, I went out and got a game with an amazing character-driven story and the best Final Fantasy Battle system to date.
edit: I do try to keep from watching any of his reviews if I have the game and haven't beat it yet - if only to keep from observing an annoying flaw that he points out.