I almost never read reviews anymore. I just buy whatever looks promising.
I use reviews like this (more or less:
Meta 90+ means I buy the game for sure if I was in the fence otherwise. If the game wasn't on my radar, I make sure to check it out.
Meta below 70 means I skip the game if I was otherwise on the fence.
Metascores between 70 and 90, for games that i was considering anyway, help me decide whether I buy the game right now, or put it further down my list and pick it up after a price drop, borrow from a friend, or rent from Redbox.
In other words, I look to reviews for some guidance in my game purchase decisions. But, in most cases, they only factor in to when I play (and how much I'll pay) , rather than if I'll play.