We still don't know if the emails were leaked or hacked - I've emailed Norfolk Constabulary to see if they have managed to get to the bottom of what exactly it is they are investigating. Given that they are treating this as a serious incident with specialists brought in to assist them, one would think that after two months they would have at least ascertained what it is they are investigating.
However, there is some new evidence, of sorts. A couple of commenters have noted interesting opinions on the issue. In the last twenty four hours, both Phil Willis, the chairman of the House of Commons Science and Technology Committee and Mike Hulme, professor of environmental sciences at the University of East Anglia, have referred to "leaked emails".
It's not proof, but these two men are in a better position than most of us to know which it is.