South Beach is a very healthy way to eat and as mentioned, not like Atkins at all. SB helps followers develop a healthy eating plan that they can stick with for life. Main staples are lean proteins, lots of veggies, beans/legumes, fruit, whole grains plus dairy and good fats. The focus is to get away from refined sugars and simple carbs (white bread/pasta) and junky foods.
Which book are you reading? The new SuperCharged contains the latest food lists and suggested interval training for faster weight loss. If you're reading the original book, check out the updated food lists here on 3FC.
I don't know about your past failed diet attempts but I know for me, I focused on losing weight more than learning how to eat correctly. That always flopped after a while. With SB I am now eating what is good for me in correct portions AND losing weight. It is a good thing.