It's just the same exact game, except the dungeons and enemies and items and spells, yadda yadda are in 3D.
The same map layouts, the same story, the same characters, the same items, the same quests... yadda yadda yadda
The -only- thing that's new are the 4 new default classes (and respective avatars for use on your custom character).
I was hoping for SOMETHING new, but I had already beat this before! Total lazy port. It's still a pretty decent game if you -haven't- played it before.