Spoiler Slayer

Just to cover a few thoughts thrown out in the comments for 'Buffy has no soul' entry.

I don't think that this is a dream, because of all the players involved. As one of the big proponents for the 'alternate reality/dream' theory for Season Five, I've gotten a little wiser to the ways the writers are working. Having it be a dream would totally strip any significant character development that is going on over these few episodes, and essentially leave us where we left off at the end of 'Tabula Rasa'. Plus, with the Troika running around, Spike's interactions with others, Willow/Amy at the Bronze, it would really not fit into the dream theory.

'Buffy is an angel', while an interesting theory, kind of brings into play a religious element that the show works hard to avoid. For example, you'll notice that it's always referred to a 'Hell Dimension', not hell. Even Buffy, only says that she thinks she was in 'Heaven', rather than actually being there. Even if she has a soul, I think they'll find some other way to explain exactly what has happened to her. Maybe there is more 'slayer' than 'soul', or maybe she has achieved some kind of immortality like a vampire has. Though again, I would bet against that, if only because that's the only thing that really stood in the way of her and Angel getting together.

As for whether or not a soul allows for emotions, I think we've seen a wide enough range in the demons that prowl this world. Obvious they can feel, have emotions, even care about others. It was also brought up about whether or not a chip could detect a thing like a soul. There are some indications that vampires (or other demons) can detect the presence of a soul. Darla, in 'Darla', told Angel that she could smell it. One can also look at 'The Judge', who could detect the humanity within a being. Also, we've seen that even without souls, Vampires do take on most of the characteristics of the person they once were. Dru's still insane, Spike's still Love's Bitch, Harmony was still a needy airhead, and Angelus was the devil-may-care hedonist. If she did come back without a soul, her Slayer instincts and own experiences would still drive her emotions. However, she would be 'going through the motions', there wouldn't be any 'fire' behind her actions. Which is exactly what we are seeing. I'm also thinking that this might not be a permanent condition, it's likely that Willow's spell was incomplete and that something could be done to restore her to normal. In the meantime, we have an excellent device to explore exactly what having a soul means. Does not having one make one evil, and does having one make one good.