Metacritic is also a great - and in some cases the only - way to get *negative* reviews. Review sites are astroturf at best and completely useless at worst. I could care less how awesome a paid reviewer thinks a product is; I want to hear about the experience somebody who paid money for a thing has had with it - if they think they got their money's worth, what pisses them off about it, etc.
Then there's the fact that with games the product is largely subjective - for example Metacritic gives Dishonored a 91 (see here) and Metro: Last Light a an 82 (see here). I've played both and personally I'd rate Last Light an A+ and Dishonored a solid D, maybe a C. Both games curve pretty similarly on graphics and gameplay - Dishonored *looks* like an Unreal engine game and the reward curve on stealth mechanics feels capricious at best - it's possible to finish a level without tripping any alarms but you still "fail" (accumulate chaos) if the guy you knocked out and stuffed in a dumpster at the beginning of the level is eaten by rats - and the end-of-mission screen is the only indicator this has happened. Last Light, on the other hand, is a similar-length game that rewards stealth but also requires a satisfying amount of run-and-gun, and is 100% pure lighting porn. It's gorgeous, immersive, and you aren't capriciously penalized for non-lethal kills - stealth mechanics are strong, realistic, and don't penalize the player with unforeseeable consequences.
I bought Dishonored based on the studio, price (sale), and alleged stealth gameplay. I didn't care for the steampunk aesthetics and found the lore intrusive - books all over the place easily triggered but less easily backed out of. The story didn't do anything for me and the art direction so strongly evoked Half-Life 2 that it felt like City 17 had been ported to the Unreal engine. I bought Last Light based on the studio and prior work of the development team, price (sale), and full knowledge of what to expect for gameplay. The story was engrossing and the art direction was film grade and incredibly immersive. Reviews contributed to neither purchase and review scores in no way reflect my experience with either game... and these are just two examples that I've played recently.