From what I've seen so far, I'm deeply in love with this game. The UI, the thought put into every aspect of the experience (character interaction, saves, NPC reactions) really makes it immersive. It's atmospheric in a pleasant, well-rounded way. I feel that the music, sound effects, and color scheme all create a world that's easy to lose yourself in. I don't know how else to describe it-- it just feels natural. 

Probably one of the first games I've played that truly made me feel like "I" was really there. The quality of the dialogue helps with that immensely, I should add.