I thought the programme was pretty inconclusive and that its hard to say with any certainty what the truth is.
However, the possibilty that he was murdered is credible enough to given serious consideration. The investigation into his death singularly failed to do this at any point - which, given Huttons track record in northern ireland and that the most obvious suspect was the security services , is not surprising.
I thought the notion that it was Iraqi security services pretty laugable and the bloke with the 'hotline to the CIA' was clearly a self publicising nob-head.
The State (whichever branch) did have a potential motive for murdreing him (one which the programme refrained from pointing out). It is quite possible that Kelly had the potential to seriously drop the government in the shit. Up until then he had just given 'off record' hints to hacks that the giovernment had lied, if he'd have gone on the record, with even more damaging facts, it might have brought Blair down. The way he had been treated by the MOD and the whitehall certainly gave him a serious grudge.
It may be that after hauling over the coals and gerreally treating him like shit, the Spooks realised he was abou to spill the beans and hastily dispatched him. I really don't think thats 'conspiraloon nonsense', I think it within the bounds of reasonable possibility and should be seriously investigated . They had means, motive and opportunity. The only sticking point is the lack of a credible historical precedent for the security services assinating someone in such circumstances - althogh they have done it abroad and in Ireland through proxys (i.e local armed groups like the loyalists gangs or the use of a militant islamist group to try and off Gadaffi).
I'm certainly not ruling out suicide. His wife - the person best qulaified to judge his state of mind (as opposed to the rent-a-diagnosis shrink they wheeled out) - believes he took his own life.
This probably balances the factors arguing agasint - the unsual method (its very difficult and very painful to hack through the main artery in your wrist - especially with a pocket knife) , the e-mails about 'dark actors', the lack of blood etc.
Open verdict. The government has his blood on its hands either way.
(unless it wasn;t security servcies but Alastair Campbell's 'extreme news management group' - who offed John Smith, Princess Diana and Robin Cook as well - dont say it was me who told you)