Allyson Felix, Jeneba Tarmoh to have runoff or coin toss in 100 - 2012 Olympics - SI.com
C Frank0 stashed this in About The Olympics 2012 London Games
The athletes choose between a runoff and a coin toss. If both athletes choose the same option, it will determine the tiebreaker. If the athletes disagree, the tiebreaker will be a runoff. If both athletes decline a preference, the tiebreaker will be a coin toss.
I'm guessing both won't choose to have a coin toss decide their fate so I'm looking forward to an exciting runoff this week.
If anyone chooses a runoff, it's a runoff.
If neither chooses a runoff, it's a coin toss, though really, they should both be kicked out. :)