The Nielsen Co.'s overnight measurement in the nation's 56 biggest cities show more than seven of every 100 homes with television sets was tuned to ESPN to see where James would play. It's expected to be the biggest audience ESPN has ever gotten for a news program.
In Cleveland, "The Decision" drew a staggering 26 rating - meaning more than one in four homes had TVs tuned to ESPN to see James say he was leaving his hometown Cavaliers for the Miami Heat.
In Miami, the show had a 12.8 rating.
ESPN is owned by The Walt Disney Co.
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LeBron Gets Cheers in Miami, Jeers in Cleveland
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Jim Gray: Dan Gilbert Will Regret Dissing LeBron
CBSSports.com's Ken Berger: Pick Changes Landscape
CBSSports.com's Mike Freeman: No Title Lock for Heat