Google's ( GOOG) tremendous run from its August 2004 initial public offering to its emergence as a tech giant with a $100 billion market cap has finally been recognized by the overseers of the S&P 500. Standard & Poor's, after passing up earlier opportunities to add Google to the index, said Thursday that the Internet-search company will replace Burlington Resources ( BR) in the S&P 500 after the close of trading March 31. Google's shares surged $25.09, or 7.3%, to $366.98 in after-hours trading. Google's addition will create demand for its shares because mutual funds whose composition allow them to track the S&P 500 will have to buy the stock. Burlington Resources is being removed because it's getting acquired by ConocoPhillips ( COP).