Wasn't there discussion about the fact that the jury couldn't conclude that Casey was the person responsible for Caylee's care...that her parents were largely Caylee's cartetaker? I don't remember it exactly, but for some reason I kinda remember something along those lines.
One of the jurors interviewed (I believe it was the foreman) said they didn't convict of child neglect because they didn't know who was responsible for Caylee. IMO, If they would have done their job, they would have asked the judge about guardianship laws instead of just saying "well, since we don't know, we'll just vote not guilty". I don't understand why the foreman thought he could just make up rules as they went along, and the rest of them went along with it.
I personally think they were hung up on the punishment, and wonder if they believed she would get the death penalty if they voted guilty on any of the murder/manslaughter charges, so they refused to do it.