Not sure about this as a weight loss diet (think that's more to do with the smaller portions) but I would definitely agree on it having health benefits.
Vinegar - specifically apple cider - is really good for flushing toxins out of the body.
Also, a full ripe banana is much, much better for you than a green/slightly yellow one. The more dark patches it has on it's skin, the better, as this means the antioxidant levels are at their highest. They say, 1-2 bananas a day increases your immune system.