Confused, you know I am
I read this issue, scanned though it, then reread it again and I am still confused what happened to who and why.
I then looked up different Wiki links to hopefully finds some explainations, and that helped a bit, but Gregg Hurwitz still had me scrathing my head wondering why did Batman do that, or who is that or why is the Mad Hatter so... and then it hit me like a crowbar to the head.
Gregg is writing this arc Mad Hatter style. The story bounds all over the place (Bruce as a child), characters enter and exit the story haphazardly (Catwoman's cameo) and the story seems to go down the rabbit hole so quickly that you are left wondering if who is really in wonderland and who is safely in Gotham.
Once you can get past the madness and except it, you start noticing Ethan Van Sciver art is pretty cool. The faceless adults have a Charlie Brown quality about them and the gore and death seem to work both as in your face and beyond panel.
So my opinion if you are ready Dark Knight get this issue, read it only when you have time to read it a second time. If are not reading Dark Knight now wait for the trade.