At the risk of giving unwavering types another fit of apoplexy, I very much agree with this comment at Biased BBC:
The Spy Who Came In from Al-Qaeda was superb. The jihadi who came in from the cold was very brave. And the reporter behind it, oddly enough, was former Newsnight reporter Peter Marshall.
(Peter Marshall's career has already been blighted though. Ian Katz unceremoniously dumped him from Newsnight a year or so ago).