Amanda Ross is flying to Miami tomorrow for a friend’s wedding, and the heads of Random House, Penguin and HarperCollins all want to know the same thing: what would she like to read on the plane? “Marley & Me,” she says. I tell her I’ve read it and she gets excited and demands my thoughts. “Not great,” I say without thinking. “Overly soppy, and the writing was clunky in parts.”

“I don’t think I’ll bother then,” she demurs, at which point I start to panic about the poor bloke who wrote it and the millions I’ve just lost him. According to one recent survey, Ross, 43 and the executive producer for Richard & Judy, is now the most powerful woman in publishing.

She chooses the titles for their insanely popular book club and her endorsement (given mostly to intelligent, mainstream fiction) is a literary elixir. Glam, plain spoken, allergic to pretension and happy to call British authors out for not being commercial enough, Ross is one of the big reasons why we read what we read.

Her influence is so thorough, in fact, that it is likely you are halfway through one of her recommendations right now. Her crop of summer choices (including Victoria Hislop’s The Island) sit at numbers one, two, four and six on the Sunday Times bestseller list. “People are saying that I’ve got too much power,” she laughs from behind the desk of her south London office, “and I’m starting to think they have a point.”

Especially telling is the current success of The Righteous Men by Sam Bourne (aka newspaper columnist Jonathan Freedland) and My Best Friend’s Girl by Dorothy Koomson. When first published the former was trashed by Michael Dibdin in The Times (“a mixture of plonking facts and breathless platitudes”) and the latter didn’t even get any reviews. But tough write-ups and total obscurity are no match for Ross’s golden spotlight. Today Bourne and Koomson outsell Zadie Smith and — more remarkably — Jordan.

The same is true of any tome ennobled by Ross: from Alice Sebold’s The Lovely Bones to Anchee Min’s Empress Orchid, they clog airport bookshops, festoon sun loungers, poke out from handbags and come with surprisingly indelible “Richard & Judy” stickers that make them very embarrassing to read by the hotel pool because strangers presume that the sticker is the reason you bought it.

But buy them we do, to the tune of £58m worth of books during the club’s last 10-week run alone. Even the show’s biggest turkey — The Conjurer’s Bird by Martin Davies, which Ross loved but guest critic Tony Robinson rubbished on live telly — sold over 100,000 copies. This was nothing to Joseph O’Connor, though. When Ross fished his Star of the Sea from the literary void two years ago it had barely sold 4,000 copies. At the last count sales were over a million.

Yet behind this phenomenon is a woman who, growing up in working-class Pitsea, Essex, owned just two books: a children’s encyclopedia and a medical dictionary. She was the first person in her family to go to university, and worked her way up the ranks of daytime TV the hard way. Later she would learn the joys of a good read, but the Essex accent and hairdo still single her out from the pince-nez and halitosis crowd that used to dominate publishing.

Ross — along with Gaynor Allen and Kes Nielsen, the book managers for Tesco and Amazon respectively — is part of publishing’s new guard. But while her peers champion a gloopy diet of D-list memoirs (Jade: My Autobiography) and sketchy fiction (Pamela Anderson’s Star), Ross cannot be blamed for falling literacy rates. She is more like a books oracle, urging disciples to stretch and expand their literary tastes.

Every year Ross (along with three assistants) hand-picks 16 titles for the show — 10 for the main club at the start of the year and six for the Summer Read. A little film is made about each one before Richard, Judy and a revolving door of celebrity reviewers, such as Bob Geldof and Janet Street-Porter, discuss them in the studio. Ross refers to this last part as “sofa chat”.

For all the sniffing directed at “sofa chat”, it has launched some of the most adored and debated novels of the era, including Audrey Niffenegger’s The Time Traveller’s Wife, Carlos Ruiz Zafon’s The Shadow of the Wind and Kate Mosse’s Labyrinth. Sometimes the books err on the facile (like Robbie Williams’s Feel), but more often they are the sort of thing that might turn up on a Booker shortlist, such as David Mitchell’s Cloud Atlas or Julian Barnes’s Arthur & George.

“Becoming the nation’s books arbiter was a happy accident,” says Ross, “and my choices are largely instinctive. They come from having produced entertainment shows for years and knowing that a good story is a good story, no matter if it’s fiction or non-fiction, or even what style it’s told in.”

Literary purists may blanch at this, but Ross doesn’t care. She’s not a great fan of theirs either, and if her success proves anything, it’s that fiction has been reclaimed from the literati.