Mostly a nutrition program. I don't think it is anything that another exercise program + strict nutrition plan can't accomplish.
Some of my facebook friends seem to do ok on it. seems hard to maintain though to work out every day at home like that.
I downloaded off bittorent. Kicks your ass physically, but I made it through the whole first work out the first time. Was fun, but I literally was so sore it hurt to lift a sandwich to my mouth to eat it for about a week lol.
Its great if your looking to get cut-up instead of gaining mass. I know a couple people who have done it and got good results. A lot of stuff involved that I wouldn't be interested in like Yoga.
You can get it cheaper (burned copies) off Ebay or Craigslist. We have it, and it kicks your butt. I dont do it as much as my wife does because the guy annoys the crap out of me. I prefer the various workouts that are free On Demand thru Comcast. Cindy Whitmarsh, good workouts and she's nice to look at!