The first thing I noticed was Narrator's new voice. They called her Microsoft Anna, and she sounded much better to me, than Microsoft Sam. I wonder, though, how much of that was the sound system. Anyway, I didn't really notice anything new in narrator that would make it a replacement screen reader. They are still supportive of the screen reader vendors.
I can't comment on the on screen keyboard or magnification features. I do know that they said that to make the on screen keyboard bigger, you would have to actually drop the resolution on your monitor. I don't quite understand why that would help any, but okay.
Then, they demonstrated the speech recognition features built in to windows Vista. This, I thought, was really cool. I could actually see it being helpful for people who have RSD in their hands. Maybe you don't want to pay for a whole program like Dragon or whatever if some days are good enough to type, or you just need help for the times when you use your computer for a long period of time. They said it was accessible, and I got the impression that this was from a screen reader standpoint. I'd have to listen to the presentation again to tell you if that's true or not. I don't have RSD in my hands, but I would consider using it for papers when I need to input quotes and such. If I'm reading them in Braille and speaking them into the paper, that would save some time.
All in all, nothing earthshattering, but cool features nonetheless. I do feel like I'm leaving something out. Anyone wanna say what that is? I'm blanking.