Thanks to Famitsu, we now know that Tales of the Abyss 3D will be much more than a simple port of the original game. We've got some screens and information introducing the improvements made to the 3D version. First is the news that the the game's skits will be redone, allowing the characters to show a wider range of expressions.
Here's a comparison of a scene on the PS2 (on the left) and on the 3DS. The 3DS has a wide screen view, showing more of the scene. The game's teaser site also attempts to get into the spirit of the 3D aspect of the visuals.
Battles and world exploration will both make use of the bottom screen. During world exploration, the bottom screen will feature a map. In battle, players can issue commands to allies using the bottom screen. The article also mentions that the 3D features in the game will make it easier to judge the difference between characters and enemies.
That's all we know about the new additions to the game so far, but here's a few more screens and some character art: