One of the early decisions we made was that a player should be able to complete any quest in the game while being a werewolf character. Since the change only happens at night, it made sense that if no NPC had reason to believe the player was a werewolf, he should react normally to him. So, NPCs will only react negatively to a player who actually changes to or from werewolf form in front of them. This allows players to truly roleplay a werewolf character-hero by day, monster by night. The careful player can still complete every quest in the game, and he can still spend half his time terrorizing the populace. It seems like a cool plan.