My wife bought me a sizable jar of Kilauea black sea salt, and it's labeled as a "finishing salt." First time I'd seen the phrase, so I figured I'd ask. Any guidelines for this? Or is the point just to sprinkle some on the food just before serving to add a little more seasoning as well as a decorative quality to the dish?

Exactly...there are many different kinds and flavorings. The store sur la table has a great selection of them. U will find u can really enhance ur dish by using these finishing salts

With finishing salts it is important to taste them first, so you get a feel for how "salty" they are. Then start experimenting by adding a bit to a finished dish. You may want to review the lesson on "How to Season with Salt" as we touch upon this a bit in that lesson. Remember to just have fun with it. Also, start with less at first, as you can always add more later. Cheers!