I read them all and I'm getting excited about this story. I'm not even a Joker fan. Most of the time I have trouble getting past the fact that no one--not the superheroes, other villains or even the law--has killed him yet. I know, it's comics but that and the fact the bat family has gone out of their way to save him are pet peeves of mine. Anyway, Snyder has promised that his story is self contained. Sounds like there will be tie ins after it's over but they don't need to be read to get the whole story. But the things I'm excited about?
The fact he mentions other bat family members being involved in this. Which only makes sense given the name. (Although neither Steph and Cass can be used.) I'm wondering how Jason and Barbara will deal with this since they are trying to get past their own traumas. I think the most unsettling thing I've read on this has been that the Joker has been missing so long because he's been keeping taps on all the bat family. Given the fact Jason and Tim having been spending a lot of time away from Gotham that's really scary.
EDIT: No, the scariest thing I read was the bit (I lost track which site had this part) where Snyder encouraged other writers to maim, kill or even have rape in their stories. This was always a problem with the Killing Joke where some assumed it happened to Barbara. I never want to see a story involving the Joker sexually attacking any of these characters.