Elder Scrolls IV: Oblivion Fan Interview #3

Bethesda's Pete Hines stopped by the official Elder Scrolls forums to post a third fan interview for Oblivion. This time around, the interview reveals all sorts of new information, including specifics about creature interaction, necromancy, in-game books, and more. Here's a bit of what to expect:
Q: We've read that it's possible for "friends" to join a faction along side you and you can watch them progress. Is this governed by RAI or is it a specific quest thing? Is it even possible to make friends like that?

A: Radiant AI is a global system that governs every action of NPCs. While we use it to do grand, overarching things like dictating how and where NPCs spend their days and nights, we also use it in much smaller sequences to do things as mundane as moving a character across a room to pick up an item. So, in a way, everything NPCs do is at some point governed by Radiant AI. In certain factions, you will meet what we term (continuing characters.) These are characters who you will come into contact with at several different points throughout the questline. You can talk to them, watch them grow, influence them, and perhaps even go on quests with them and alter their paths through the game.