With great power comes responsibility.  With a 59% interest, Larry and Sergey had absolute power over Google, and therefore absolute responsibility.  Perhaps the move in China led some to believe that this is too much power.  52% enables the remaining shareholders to overrule Larry and Sergey's decisions -- in theory.  In order for this to occur, virtually all the remaining shareholders would need to reach unanimous agreement against a decision made by Sergey and Larry -- highly improbable, but <i>possible</i>.  Without absolute power, there is no absolute responsibility.  Conveniently, this also aligns with a liquidation of billions of dollars.