Oh, I agree. It's great to have him there as an idea, like God, but not as an actual being. It's more effective to leave angels and God and the Devil as concepts based in faith that may be real but may not. Otoh, demons are of course the flipside of angels and they're obviously real, so why wouldn't angels be? Anyway though, even if angels and demons are real, I don't want God or Lucifer to be confirmed as real... that'd be kinda lame. I just like the idea of demons having faith in Lucifer, it's neat. :)

Maybe... well, I'm not thinking of it being exactly like Buffy; I just prefer the idea of Sam becoming colder and darker being character-based, not demon-based. It's more interesting, imo. Though I suppose it'd be interesting, too, if he becomes darker because of the demon blood. Maybe it'll be a bit of both - the demon blood is the catalyst for the things he's going to do, and it enhanced those character traits that he already possessed.