As one who has done the Atkins diet (actually Protein Power, but there's not much difference), and as one who has been in moderate ketosis and lost 30 lbs in 3 months (20lbs in the first month), I can say that low-carb dieting is great for losing weight fast.
That said, it's not something I would do long-term, and in fact, I wouldn't recommend it even short term. Reducing carbs in general I think is good, but eliminating them is not so good, especially if you eliminate fruits and vegetables in the process.
Being on the Atkins diet is what I think brought me to this forum. By that I mean, I blame my rapid weight loss for my gallstones. I probably would have gotten them eventually, but if you believe what the Western doctors say, Gallstones are typically caused by rapid weight loss. I know that I never had pains prior to losing the weight. 1 year after losing the weight... I have gallstones. I can't say it was a definite cause and effect, but it's likely. So, I recommend some reduction in carbs, exercise, and try not to lose more than 2 lbs. a week. Oh, and flush that liver too! :)