Looks like I missed the first airing but MTV 2 is airing the Ulimate Parkour challenge on 11/07 at 11:20pm eastern time(Comcast ch 273)
L'art du deplacement. The art of moving. The object is to negotiate obstacles in the most efficient way possible using only the human body and the obstacle.
I think I remember it as being developed by the French Military, but I may be off base there.
I've made the decision that this discipline would probably lead to my death or serious injury so I admire the art from afar. However, if you research the training routines you'll pick up lots of great body weight exercises and outdoor training. It's a great way to change up your workouts.
Free running is another Americanized Parkour form. I like the original term Parkour because the French are sooo French and it's cooler to say Parkour than some of the other names. Although Free Runners or ing sounds good also.