Reading through the earlier posts, I have to address some mistaken perceptions. It is entirely possible to embrace ultralight backpacking on a Philmont trek. Some crews do, many do not. Remember we're talking about teenagers, many of whom may not have the time, money, or interest to tweak every last ounce from their kit. Priorities are different at that age.
Philmont has equipment available for use, usually expedition-weight, but does not require its use. Our crew brought all of our own equipment on our trek last year. Philmont has a few specific requirements, like use of bear bags, no open-toed shoes on the trail or while cooking, and fully enclosed tents - not floorless - to avoid safety issues like waking up with a rattler in your sleeping bag (found one under my ground cloth one morning). Scout uniforms are required for travel to/from Philmont, but are not required and almost never worn on the trail.
Some extra weight is also due to insurance - adult advisors are responsible for health and safety of the teen crew, and many coach a few extra pounds of clothing and equipment for unexpected circumstances that inexperienced backpackers frequently don't consider...like sub-freezing morning temperatures at Copper Park on occasion.
For those looking for lists, here's a link to Selden Ball's Philmont website, the comprehensive index of all things Philmont.
Section 126.96.36.199, entitled "Lightweight Packing" has a half-dozen links to equipment lists from a number of adult advisors (and the first link in the list is to BackpackingLight.com!) I used Dr. Bob's list as a jumping-off point last year and it served me well. (http://www.troop111.org/phil02list1.html)