Apple re-overtakes Exxon Mobil by Philip Elmer-DeWitt @FortuneMagazine August 10, 2011, 3:17 PM EST E-mail Tweet Facebook Google Plus Linkedin Share icons The computer maker is once again the world’s most valuable company As the Dow Jones industrial average plunged another 500-plus points Wednesday, Exxon Mobil XOM plunged more than Apple AAPL and once again gave up its long-held spot as the No. 1 public company in the world in terms of market capitalization. When the closing bell rang, Apple closed on top for the first time. The tale of the tape looked like this: Co. Price Change % Market cap Apple $363.39 -10.32 -2.76% $337.17 B Exxon $68.03 -3.14 -4.41% $330.77 B On Tuesday, Apple’s market cap (share price times number of shares outstanding) briefly overtook Exxon’s, although Exxon ended the day ahead. See here. One day later, Apple became the world’s most-valued company by a cool $6.4 billion.