Assuming the game does even moderately well, which is looking more and more likely, we plan to keep enhancing it for years to come, especially in terms of MP and social gaming.
Hell, I'd like to see people make their own quests and campaigns and share them. The campaign Jon Shafer has made "The Fallen Enchantress" was done entirely with built in tools (i.e. no special programming) and it's insane in how complex you can get.
Seriously, go back and play Baldur's Gate and look at it carefully from what it does. Obviously it's a masterpiece of story and content. But feature wise, it's not really beyond what a modder could do. Now, imagine a co-op campaign where the players are in the same world but in different places.
These are not promises, mind you. This sort of thing takes money and time to do. But it gives you an idea of what sorts of things we'd like to do.