The package says "Certified organic cacao". It does not include any additional ingredients. It tastes like nutty chocolate chips, which I blend into my morning smoothie. I keep buying them. Hope this helps answer your question.
The obvious difference is the ingredients, but I'm sure you read that already that the sweet ones have certified organic sugar cane juice (Saccharum officinarum) and certified organic cacao liquor (Theobroma cacao). So the regular ones taste more nutty and less like a chocolate snack. The regular nibs quickly satisfy your hunger because they are so nutrient rich as opposed to eating sugar which typically gives you hunger cravings. The natural nibs can be slightly bitter, though nothing like whole cacao beans with the brown husk, which is much more bitter. However, if you eat the natural nibs with something else (I soak them along with goji berries for my cereal in the morning) such as some nuts, raisins and goji berries to make your own trail mix, you won't notice any bitter taste at all. They are good by themselves once you get used to them, but I probably wouldn't eat them as a snack by themselves. But I love them on my raw buckwheat cereal. That's one person's opinion, hope it helps.