It cannot be argued that low-carb diets are not superior for pure fat-loss (yes I said that right!). When you're body makes the "metabolic switch" to burn fat instead of carbs, as its primary source of fuel... I don't know, DUH!?!?!
Fat loss comes fast, and not much can slow it down, as long as your body doesn't "switch back" to a carb burning metabolism.
And don't think that I'm ALL FOR LOW-CARB DIETS, because I'm definitely NOT!
Just like any diet, where you lose lots of weight quickly, the possibility for rebound weight-gain exists. And it exists BIG-TIME with low-carb diets. Because you deprive yourself of all the foods you love so much, you tend to binge on them as soon as you can. And when you do, you'll see yourself gain back everything you lost in record time!
Going from a normal diet to a low-carb diet doesn't take much transitioning - in fact, the quicker you make the shift, the better. However, switching back is much, much trickier. You MUST gradually, and very gradually, increase your daily carb intake; and at the same time lower your fat intake.
Another note on low-carb diets: they MUST be "Low Carb/High Fat"... NOT "Low Carb/Low Fat!!!!!" Your body can not make the metabolic shift to a fat-burning metabolism if you do not eat a sufficient amount of fat (like 40-60% of total calories). If you try to do a "Low Carb/Low Fat/High Protein" diet, you'll just be tricking your body into thinking that "Protein" is your primary source of fuel and you'll eat away muscle faster than anything.