The guys at Sorcerer's Place were able to corner Ossian Studios' Alan Miranda, Luke Scull, and Kevin Smith for a lengthy interview about their upcoming Neverwinter Nights 2: Mysteries of Westgate module.
SP: Is the tiredness system from Darkness over Daggerford also in Mysteries of Westgate? What other restrictions or realism adjustments will players experience in the adventure pack, which weren't in the official campaign?
Kevin Smith: Although there are resting restrictions in several unsafe areas, there is no general tiredness system in Mysteries of Westgate. On the other hand, we did use a custom NPC ambient system to help bring the city to life. When compared to Daggerford, I'd say that MoW has more realistic NPC AI. Many of the foes that you encounter in MoW employ custom-scripted AI during combat. This not only makes them more realistic but also much more deadly. Even some of the minor combats against relatively insignificant foes feature custom AI.