Matthew Bell: The IoS diary

In an extraordinary move that will undermine the work of journalists worldwide, the trustees of the late Hugo Young, the esteemed political columnist of 'The Guardian', are to publish his private papers, in which he recorded what establishment figures had told him off the record. Penguin, which publishes the book in November, boasts: "Most of [Young's] interlocutors were unaware that straight after their telephone conversation, meal or meeting with Young had finished, he meticulously wrote down exactly what had been said." Young's interviewees included politicians, judges and senior civil servants, and many are still alive. In accordance with professional journalistic practice, they would have spoken to Young freely only because they thought what they were saying was off the record, and would remain so. Ion Trewin, a friend of Young's from the 1960s who selected the passages from the 1.5 million words in his papers, refused to comment on the ethics of the book. "I am uncomfortable talking about this," he told me. "Frankly it's not for me to comment. I am not the book's spokesperson." Will anyone be able to trust a 'Guardian' journalist ever again?

The whips ordered every Labour MP to hit the campaign trail in Glasgow East prior to the by-election, but former sports minister Richard Caborn must have felt he had done all he could, come polling day. He was spotted catching a lunchtime train from Doncaster to London – first class, of course – with a large portmanteau of official documents. While many were fretting over the impending disaster, I gather Caborn spent his journey grappling with 'The Independent' sudoku. A case of puzzling while Glasgow burns?

While switched-on Labour supporters foresaw disaster at Thursday's Glasgow East by-election, YouGov president Peter Kellner was unfazed. "Calm down, dear, it's only a by-election," he wrote on the Fabian Society website the day before. "To say that Labour must win the by-election for Gordon Brown to remain Prime Minister is politically daft." We shall see. But Kellner's is hardly the voice of dispassionate impartiality, either. Mrs Kellner is Baroness Ashton of Upholland, Gordon Brown's close ally who leads Labour in the House of Lords. Older dears will recall that before subscribing to New Labour, Cathy Ashton worked for CND.

You might have thought Barack Obama would have been as keen to court the British press as he was Gordon Brown when visiting London yesterday. But he took only two questions from British journalists as he emerged from No 10 (one of which – "Is there still a special relationship?" – should win some sort of dimness prize). The Americans were allowed rather more, although they were hardly at their sharpest. Not only had they followed Obama throughout his supernova 10-day overseas tour, but many had been out partying in Soho until 4am.

Mick Jagger's clean living has been much mentioned on his 65th birthday, as has the Rolling Stones' move from EMI to Universal. But some things never change. In order to make their switch of record companies, the band had to sign a lot of legal papers. I'm told it took three days to locate Keith Richards.

Spotted at Glyndebourne: opera buff and former MP David Mellor, enjoying a production of 'Hänsel und Gretel'. At least, he enjoyed the second half. During the first he and his female companion were seated in front of an excitable little girl, who, like many, was distracted by a bat that was circling the auditorium, adding a certain spooky realism to scenes involving the witch in the woods. Alas for Mellor, the excitement was too much: he asked to move seats during the interval.

Baroness Thatcher's former press secretary Sir Bernard Ingham is among those to be immortalised in a BBC drama 'Margaret Thatcher's Men'. Sir Bernard is being played by Philip Jackson, best known for his role as Inspector Japp in 'Poirot' alongside David Suchet. "I have watched 'Poirot' but I don't really remember Inspector Japp," Sir Bernard tells me. "This sort of thing was bound to happen. The BBC keeps treating politics as entertainment. No doubt I will be fascinated, if I watch it, to see if anything in it bears the slightest resemblance to reality."

A market trader on Golborne Road, west London, was hoping to make a little extra from sales of second-hand bikes yesterday morning. One had a picture of David Cameron attached, together with an unusually high price tag of £60.

Question: which female member of the Cabinet has a full-size Dalek in her sitting room? A bottle for the first correct answer, to be revealed next week.