Sony paid for the high LBP reviews on Gamerankings and Metacritics. The sales of LBP have been below expectations. Bundles of the game should help a bit though and it could sell 2 million copies over its life time.
High game reviews are bought by companies to sell their games and help generate hype to boost sales of the game. All three companies Nintendo, Sony and MS have paid for high game reviews over time to help boost sales of games.