I've seen a lot of people on these boards get scolded for referring to a 5,000m on the track as a "5k". The scolders write, "It's not a turkey trot. If it's on the track it's '5,000m'."
Well, now we know the American record holder called it a 5k, too. So from now on, unless Lagat wants to rescind his comment, you're all allowed to refer to 5,000m on the track as 5k.
You're welcome.