- Emotions - lizard-brain reactions to environmental stimuli
- Perception - awareness of environmental features
- Communication - ability to transmit state information or knowledge to other NPCs
- Memory - awareness of previous encounters as positive or negative toward the NPC's plans
- World-knowledge - understanding of thing-behavior and people-behavior in the world (as in Doug Lenat's Cyc project)
- Planning - ability to propose actions to achieve low-level, immediate goals and high-level, long-term purpose
- Self-reasoning - ability to effectively describe internal states and knowledge
But it would, I think, lead to a very different gameworld than the kind we see in MMORPGs currently. Fully simulating intelligent actors and an adaptive ecosystem is probably a little too much to ask, but wouldn't MMORPG gameworlds be more interesting if we could move a little closer to those goals?
Do we really need another game where mobs are either invulnerable quest-dispensers or loot-bags existing only to be popped?