I don't know how much detail i can go into but the program is in 6 two week segments. It starts with single sets of all the exercises. Really good for just getting used to the TRX and prefecting your form. As the weeks progress the reps increase, rest decreases, multiple sets. More difficult movements are built in, such as the body saw and suspended pike. The body saw is the used to preload various exercises giving them more power. Power is also built in to leg exercises by actually jumping off the ground, something potentially dangerous with weights and machines but far safer on the TRX. You've also got supersets included which really challenge muscular endurance. By the end you're doing 3 sets, high reps, little or no rest.
When i first got it i thought 'oh, this doesn't look so hard'. Man was i wrong. With all these added anaerobic elements and endurance challenges i'm often drentched in sweat at the end of a work out. Something i'd never managed at the gym other than on the treadmill. Doing so much with the same equipment allows such quick transitions from exercise to exercise.
The program is also based on the model of doing the hardest exercises first, and using the fatigue from previous exercises to add difficulty to relatively easy exercises when done alone.
I hope my description was detailed enough to help, but not so detailed to get me in trouble. 
Max