There are many differences in the game which are not immediately viewable through screenshots. It is true that there are many graphical changes. Most effects have improved a lot and there is the improvement of general graphics but this really only applies to the 3D graphics although some item screenshots seem to have increased in quality since the last game.
The main notable difference is that where as the last game was very homebrew about Dungeons and Dragons (e.g. you could reach level 70) this one isn't (the top Dungeons and Dragons level is 20). This one became what could be literately called Dungeons & Dragons in Video game form. They actually nailed every detail into the game and made sure they were accurate. I would not be surprised if someone used this to do a Dungeons & Dragons Campaign entirely on the program.
While on the topic on custom creation, I did not use it a lot as it seemed complicated from a going from zone to zone aspect, However setting items was easy and easily done. At the moment I am having trouble with multiplayer and I would like to ask any experienced multiplayer who has NeverWinter Nights 2 to please explain in detail what I need to do.
There were a few touches which are necessary to, in my opinion, make a good RPG game. One of the most noticeable is that the choices you make with other people can mean that you gain or lose influence with the person you supported or disagreed with. I have yet to see this be crucial but will report on this later. Without going too deeply into the official plot line I would like to note some changes that I think were for the better. For one thing, in NeverWinter Nights 1 you started as a famous yet not-famous-enough-to-actually-have-decent-resources-without-paying huge-amounts-of-money character. In this version you are humble farmer's foster son and as such have to earn respect rather than buy respect. Also companions choose to go with you and do not have to be hired.
I believe that is all I can say but as my last point I would like to give the game 4.5 out of 5 stars. The only reason it did not receive 5 stars is because of the at the moment frustrating multiplayer interface.