Basically. They all have differences of course. Ideal Protein is more of a type of diet. NLD and Medifast are pretty similar, but you can use NLD for IP and Medifast. Dunno about Take Shape, never looked that one up. I know a lot of people prefer IP, but use alternative products, such as that from Diet Direct, Pro-Protien or various other sites.
All of them proclaim you can lose 3-5 pounds a week. All of them are pre-packaged meals. Some taste okay, some horrible, some pretty good.
But basically, yeah. I think IP diet type (I'd buy the alternative products..mucho cheaper) is the better of all of them though...more "real food" (read 4 cups of veggies a day
)