Interesting excerpt which seems to imply that parkour is not limited to utilitarian movement, perhaps even obliviating the distinction with freerunning:
Nicole Powers (interviewer): With parkour there also seems to be a connection to your inner child. If you look at the way a child walks along a pavement, the last thing they want to do is walk in a straight line. They want to jump across cracks in the pavement or play stepping stones, and if there's something to jump up on, instinctively they'll want to jump up on it. Parkour seems to be very much about getting in touch with your inner child and taking the interesting way, rather than the easiest route.
David Belle: I think you summed it up in a nutshell. That's what it is exactly. That's the first time anybody has given me the proper definition of parkour. Bravo Nicole!