From massages with a one-time topless model to power-hungry men desperate to stamp on their rivals' ambitions, the latest political memoirs appear to have taken their inspiration from trashy airport novels.

After John Prescott's revelations that he had not only been employed as Deputy Prime Minister, but full-time peacemaker between his boss Tony Blair and Gordon Brown, and his admission that he had fought a 10 year battle against bulimia, this year's season for settling scores and exacting revenge in the name of the serious political memoir was declared open.

Hot on the heels of the MP for Hull East came Cherie Blair. Extracts from her autobiography have so far covered everything from her youngest son's conception in a bedroom of Balmoral castle, her friendship with Carole Caplin and why, despite the barrister's income and multi-million pound property portfolio, she fears poverty.

Which brings us to Lord Levy's outpourings. Labour's former chief fundraiser became embroiled in the cash for peerages row and, while much of A Question of Honour is a final rebuttal of the allegations of which he was eventually cleared, he also tells us that he advised Blair against massages with Caplin, and that relations between the then PM and his Chancellor weren't exactly of the warm and cosy variety.

The three have collectively delivered a little over 1,200 pages, but have they really come good on early promises to lift the lid on what really goes on in Westminster and provide warts and all accounts of the political world's movers and shakers?

"I honestly think that on the evidence of these three books, the political memoir is less salacious, controversial and revealing than it ever has been," says Iain Dale, political commentator and owner of Politico's bookshop. "I may be wrong, but I don't think it has come as much of a shock that Tony and Gordon didn't get on or that Lord Levy thinks he did nothing wrong. The only real revelation was that John Prescott suffered from bulimia and I think most people would probably have lived without knowing that.

"When it comes to political memoirs there are often so many vested interests that it's difficult to get to the truth. Tony reportedly vetted Cherie's book, presumably taking out the most embarrassing bits, Lord Levy seems to have had one agenda which was to promote Lord Levy and John Prescott had a ghost writer, which puts an entirely different spin on things."

For those who feel their life in the political spotlight was overshadowed by rumours and unfair controversy, penning an autobiography is a tempting opportunity to set the record straight and, with the most influential figures commanding large advances, the rewriting of history can also prove lucrative.

Cherie was reportedly paid £1m for Speaking For Myself and with her husband having also secured a deal worth an estimated £4.6m with Random House for his memoirs, the couple have been handsomely rewarded for their decade in Number 10. In recent years, big money contracts have become the norm, but paying top dollar doesn't always guarantee returns.

"Very few memoirs would be viable either for the publisher or the author without securing a serialisation deal with a big newspaper," says Dale. "However, once you take out the handful of best bits, some autobiographies can start to look a little thin.

"It's not unknown for newspapers to buy the serial rights for a six-figure sum and then never actually print a word, and publishers really ought to be stricter with their authors.

"Editors should have the guts to say, 'This isn't what you promised, sorry, but you're going to have to do it again'. Prescott, for example appears to skim over the Tracey Temple affair as if it were a minor episode in his life rather than one which hastened the end of his career. Not telling it as it was seems to me to be a bit of a cheat.

"Ultimately what sells and what doesn't comes down to whether the public like or respect the author, and people are only going to part with £20 if they are confident you're going to learn something new. Some people respect Cherie Blair in terms of what she has achieved in her career, but she has never come across as particularly likable; most people outside the Westminster village aren't entirely sure who Lord Levy is, and I'm not sure how widespread the interest in John Prescott really is."

The desire to put pen to paper once free from the controlling influence of Chief Whips, aides and spin doctors is nothing new. Eighteen members of Margaret Thatcher's cabinets, including Geoffrey Howe, Michael Heseltine and Norman Lamont, published memoirs, and no doubt some of the current incumbents go to bed dreaming of catchy titles and opening lines for their own autobiographies.

However, while writing a memoir may have become a rite of passage for politicians and a select group of backroom staff, predicting the bestsellers is not so easy. Given some of the headlines he made while he was in office, Bill Clinton's 900-page autobiography should have been a page-turner. Unfortunately it failed to live up to expectations, while on this side of the Atlantic, potentially explosive memoirs from Robin Cook, Clare Short and David Blunkett also failed to set the literary world alight.

"It's true that it may have been easier in the past to write successful memoirs, because the private lives of politicians and what went on behind the scenes were shrouded in secrecy," says Iain. "Now we already know so much about what goes on, about who gets on with who that it can be difficult to be truly revelatory.

"Diaries tend to be more successful because they have a sense of immediacy and are written by someone who doesn't know the end. Alan Clark, Tony Benn and, much to my surprise, Alastair Campbell all produced fascinating diaries, but it doesn't always work.

"David Blunkett is an interesting character both personally and politically, but his diaries were dreadfully dull. I think I am among the few people who read them from beginning to end and all I was left with was the feeling that they had been written after the event.

"I'm not sure you could class Piers Morgan's diaries as wholly political because there was so much else in there, but I honestly think his was one of the best books of recent times. He may not be particularly likable, but he is controversial, and when it came to giving little nuggets of genuinely entertaining stuff he delivered where many politicians fail. As for straight autobiographies, John Major's is up there with the best. He may have been portrayed as the grey man of politics, but his book showed he was an altogether more interesting character, and that's what readers want."

No date has yet been set for the release of Blair's memoirs, although his successor is probably keeping his fingers crossed that it isn't any time soon. Just how honest he will be remains to be seen, but to get the most enjoyment out of the political memoir, Iain advises to treat it more like a work of fiction than a historical document.

"I have quite high expectations of Blair," he says. "Of course it will be partisan, but then what political memoir isn't it?

"What you have to remember is that the political memoir is written some years after particular events and inevitably individuals remember the
past differently.

"We want people to spill the beans and to reveal exactly what they thought about their colleagues and their opponents. In short we want them to be candid. The best memoirs do offer a fascinating glimpse into what makes a person tick, the honest truth about events over which they presided – and if you can throw in a little scandal, it really is the perfect mix."