I should steal that "spinning siren" that Matt Drudge uses for stories like these. Anything Steven Munatones writes about open water is worth it In this update, Steven goes into specific details as to how and why Grant Hackett was DQed.
Swimming World update: "... The second infraction was committed with less than 250 meters from the finish in the mad dash to the finish. When the pace picked up with less than 1000 meters to go, Hackett was caught in the middle of the surging pack. With every stroke, unintentional collisions were made due to the close proximity of the swimmers to each other. As Hackett tried to create more space between himself and the swimmer alongside him, he apparently slowed down and tried deliberately to go over the back of Chip Peterson's legs. Apparently, the degree of separation between Hackett and Peterson was not enough. Unfortunately for both swimmers, Hackett swam over Peterson in a manner that three referees believed impeded the progress of Peterson. ..." [Link]
You would think that Grant Hackett would have swam like my favorite Russian, Larisa Ilchenko, by surging to the front and staying there. I bet Chip Peterson was pissed about the infraction but then again, look what it took to bring him down, the greatest distance swimmer of our time. Chip will still make it to Beijing I bet.