I only have Harley and Joker, as I've said elsewhere, but I'm mighty tempted to pick up Poison Ivy as well. Such a great looking figure.
If it was still back in the day when I was a hardcore DCD collector, I'd happily grab them all, but I very rarely buy action figures these days, unless I see a Harley or Joker piece I really like (as I still have a dedicated Joker 'n Harley shelf set up and on display). But it's lines like this one that tempt me to start up that old DCD figure collecting habit again on a wider scale...
Oh, by the way, I must have missed it, but do we know the line up for Arkham City series 1 yet? I know we've seen the Harley two-up, but can anyone fill me in on what else to expect there (if we know)?