It's all about scarcity of resources

There has been rumours going on for quite sometime that Google has started to lower their requirements to new hires(unfortunately I cannot remember where;)), but as it is apparant from this article it seems that Google still have some of the "smartest guys in the room". Nevertheless, as it is apparent from the citation below to many smart people may cause problems...

Every company wants to hire the smartest people possible, and Google has clearly succeeded. But you know what you get when you get too many smart people in one room? You get the corporate equivalent of the U.S. Olympic basketball team.

Think about it: there can only be one smartest person in every room. There are dozens of trophy hires and incredibly smart, entrepreneurial minds buried inside Google who are fast-becoming frustrated with their inability to accomplish anything. And while Google motors along, minting money with its AdSense and AdWords programs, these brilliant minds are getting antsy.

Armed with seven-figure bank accounts and professional networks of dozens of other equally brilliant and rich new friends, those frustrated Googlers are bound to
set out on their own and ignite a son-of-Google wave of innovation.