"Imprisoned and killed without trial..."
I see the sensationalism has already got you salivating. I know all this "Prisoner X" thing and the possibility this Ben Zygier guy was Mossad can capture the imagination - and hey, there may be room for a Litvinenko-scale conspiracy here - but facts carry stories, not speculation. The official story is that he was imprisoned, tried, and comitted suicide. Whether or not you believe this is irellavent because at this stage this is all the information we have.
Even the Coalition is left short of ammo in regard to using it to attack Bob Carr or the Gillard Government. They know as much as the rest of us. They may want to criticise Carr for his very slightly changing story as to when the Australian Government was made aware of the situation but really despite it involving an Australian citizen it's an Israeli matter - and I doubt they will be particularly forth-coming with the details.
There very well might be a deep dark story here and there'll be a few articles questioning a cover-up in the Daily Telegraph I'm sure - and admittedly it seems likely something questionable may have taken place. But things of this nature require actual investigative journalism to flesh out and investigative journalism is not exactly the Australian media's, (by which I mean predominantly Fairfax and News Ltd,) strong point. Unless something new comes out I give it less than a week.