I am about 5 hours in and I am enjoying this game. The music is great and adds to the atmosphere. The game just looks amazing, and when I was watching the opening cut scene though... it won't look this good once this is over. Nope, wrong. It's beautiful!
I also love the "shared feature" of the game, where other players can "help" you by leaving objects (ladders, ropes, signs, etc) behind to help you navigate the world. I have "liked" so many player's structures. If you play, don't forget to "like" as well!
I thought that wandering around being a currier might be a bit boring. But between the atmosphere, beauty of the game, music and looking for objects along the way (and watching out for the big bad) it's anything but boring.
Overall, I think it's a great game so far and I can't wait to play more!