My girlfriend was watching a Let’s play of the game Fez. It is mostly a 2D platform game. Though, the twist is that it is actually in a 3D-world. And your character happens to receive the power to change his perspective. The game has really good graphics, but more importantly, these graphics are voxels. So it seems that they are using a cubeset (3D-tileset), rather than 2D tilesets. And while they still don’t have a fully seamless cubeset, they come pretty close.