Wikipedia states, "The taste of pure coconut palm sugar resembles that of brown sugar, yet with more rounded caramel and butterscotch notes, without the metallic ending flavor that brown sugar has. It has a rich flavor." (http://en.wikipedia.org/wiki/Palm_sugar)
Palm sugar is not a calorie-free sweetener. It has calories like any carbohydrate, but due to its relatively low glycemic index, its calories are absorbed into the bloodstream at a significantly slower rate than regular refined sugar. This property should be of interest to anyone who is monitoring their blood sugar levels and attempting to avoid blood sugar spikes. Palm sugar isn't medicine; it's a food with a surprisingly low GI, considering its sweet taste.
This are some of the information that I gathered so far. But I bought my palm sugar in an Asian store and I love the taste of this palm sugar. I would definitely buy the big jar.