No.  You're confusing correlation with causation.  You should also consider that:

Someone plays the game before purchasing and forms their own opinion.

Some make purchases based a friend's opinion, rather than a critics.

Someone makes a purchasing decision off of a preview, rather than a review.

Someone makes a purchasing decision based off of an advertisement.

IGN has shown how little their reviews affect sales, I'd dig up the study if I weren't so lazy.  Review scores are mostly for fanboys like us to fight about.

I'd say quality affects sales more than a journalist's opinion of that quality.

I have Gamefly as well, excellent service I agree. I have Tales of Vesperia and Infinite Undiscovery on the way soon.

Won't rent Fable II though, I may be a bit short on cash but I must own that game, it deserves that much.

As for the LBP/MGS4 comment, I see what you mean with the apples and oranges comment, both are awesome, best in their respective genre in my opinion. Although if I had to just choose one, I would go LBP without hesitation.

4players.de 92% (german site)

btw the highest rating they've ever given is 94%

Says ultimate_123 AKA "LBP will be 65-80 average"

 OK I admit it. I underated the game. Fine OK happy? At least I admit when I'm wrong unlike fanboys.