Dungeon Siege 2 will, apparently, force the player to keep track of objectives, clues, and dialogue to finish the story. DS 1 did not.
I don't care, anyhow. If they made DS2 like DS1 with more content, I'd be perfectly happy. I liked DS1.
The changes that Battlewookiee has mentioned sounds as if they will improve the game, but time will tell, I suppose.