Pac-Man runs aren't calculated by score -- the highest possible score you can earn on the game before encountering the kill screen has been reached a number of times before. Instead, the record is calculated based on how quickly one can achieve a perfect score -- a record that was recently smashed by David Race, who reached the kill screen with the max score in 3 hours, 41 minutes and 22 seconds.
Race's time beat previous record holder Chris Ayra by 42 seconds -- who, in turn, had previously beaten King of Kong's bearded antagonist, Billy Mitchell's fastest time. We smell the makings of a sequel for the aforementioned, critically acclaimed 2007 documentary. The Mack of Pac, perhaps?