While the quest structure certainly isn't, the world, its presentation, and the breadth of the interactions you can have certainly feels next gen.
The real-time physics in the game is also really great, and it adds a lot of feedback - especially to the combat - that is lacking from a lot of other games, especially last gen. Heck, even the hair physics is pretty good.
Dropping both barrels into a room full of Ecliptic and watching the chaos as everything is bounced around is a delight. I also like that a lot of "dungeons" aren't interior spaces; they're right there on the planet in the open, allowing for much more freedom in how you approach them.
The visuals also feel pretty next-gen at times - interior spaces in particular. It's all real-time, with a decent GI approximation, crazy amounts of geometry and real physical objects everywhere, each with their own terrific materials and textures.