75% is pretty standard in Europe. I've tried a couple of 99% cocoa chocolates too, but these are really for the hardcore lovers (gets glued to the teeth and other taste issues).
Because you're not supposed to chew it (I believe that's even written in the "tasting tips" on the Lindt packaging at least). Bite off small bits and let them melt in your mouth. It's kind of like a dark and very tasty coffee, if that sounds good to you, give it a try.
Now if only I could find it in the supermarkets around here... (as is common in France)
