I have a friend at work doing it - so I can tell you a bit of what she's shared with me. She can have salad and vegies, but only certain ones and only so many times a week, I know carrots are on the not very often list as she loves carrots and wasn't too happy about that!
From what I gather, she has a shake for breakfast and a meal bar thing for lunch She says she's not hungry and has lost about 8kg I think in the past 10 weeks or so. You are also supposed to exercise. She looks good and you can definitely see the weight loss.
Not sure how long you could keep something like this up for though - personally I couldn't do it!