Playing Neverwinter Nights 2 is more akin to playing Baldur's Gate II or Planescape: Torment than the original Neverwinter Nights. Fully controllable and equippable party members make a return, which makes a big difference for the single player portion of the game. We'd been told a significant chunk of developmental focus was being given to making NWN2's solo campaign more involved and after playing it for around 20 hours, it's proven to be a more entertaining experience.
Fans of games like Baldur's Gate and KotOR will be happy to know that the depth of character interaction found in those milestone RPGs is present in Neverwinter Nights 2 in top form. Through the expansive dialog options available in most interactions, you're able to role-play your character in a variety of ways -- principled, miscreant, reserved, rambunctious, or what have you. Also, depending on what "social" skills you choose -- such as bluff, diplomacy, or intimidation -- you can change the outcome of certain scenarios, to the extent that you can even bypass combat in many situations. What's more, most of the characters that you can enlist have stories and conflicts of their own, and depending on how much work you put towards nurturing your relationship with them, you can experience encounters and scenarios unique to them.