This is one of the few things from the patch that interested me, so it was the first thing I did when I logged in today. I picked up a boarskin map from a level 50 mining node outside of Camp Bluefog and the help text told me to go to Wineport to do a short quest. The quest gives the abilities Decipher and Dig.
Anyway, I found my chest and opened it. When I did, I had to fight a level 50 Mantis, two level 50 Diremites, and two level 50 Wasps. The Mantis was the only one with much HP, so once it was down, the others dropped quick. My reward was quite a bit more than I expected. I picked up 9 Myth tomes, an Aetherial Raptorskin Voyager's belt, an Eagle Feather, 4 mega-potions of Strength, 90 fire shards, 2 pieces of Rosewood Lumber, 2 bottles of Spoken blood, and 5,076 gil. That's a pretty nice haul for a single player reward. I've got to get in on one of these four person maps next.